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PubMedDate not supplied

Spousal similarities in fruit and vegetable consumption.

PURPOSE: To explore similar patterns of fruit and vegetable consumption between health center employees and their spouses. DESIGN: Cross-sectional mailed survey assessing frequency of fruit and vegetable consumption, as well as demographics and knowledge, attitudes, access, and social support related to fruit and vegetable consumption. SETTING: Six Massachusetts health centers. SUBJECTS: Two hundred eleven health center employee/spouse pairs (422 individuals). MEASURES: The kappa statistic measured agreement in fruit and vegetable consumption between employees and spouses. The Spearman rho coefficient measured correlations for individual responses. Multiple Linear Regression Models examined variables that explained fruit and vegetable consumption level differences. RESULTS: Response rate was 59%. Mean fruit and vegetable daily intake was 4.68 and 4.30 servings for employees and spouses, respectively. Over 75% of employee and spouse estimates measuring fruit and vegetable consumption-related information, on average, were within one survey response category of each other. Knowledge, attitudes, and access indices were significantly correlated with fruit and vegetable consumption for both employees and spouses. The social support index was significantly correlated with fruit and vegetable consumption only for the spouses. Differences in knowledge, attitudes, and access indices between employees and spouses helped to explain different fruit and vegetable consumption levels. Nonresponse, selection, recall, and seasonal reporting biases may limit the findings' generalizability. CONCLUSIONS: The effectiveness of worksite nutrition interventions may be improved by involving family/household members.

Adult↗
PubMed1999

Lifestyle modifications to prevent and control hypertension. 3. Recommendations on alcohol consumption. Canadian Hypertension Society, Canadian Coalition for High Blood Pressure Prevention and Control, Laboratory Centre for Disease Control at Health Canada, Heart and Stroke Foundation of Canada.

OBJECTIVE: To provide updated, evidence-based recommendations concerning the effects of alcohol consumption on the prevention and control of hypertension in otherwise healthy adults (except pregnant women). OPTIONS: There are 2 main options for those at risk for hypertension: avert the condition by limiting alcohol consumption or by using other nonpharmacologic methods, or maintain or increase the risk of hypertension by making no change in alcohol consumption. The options for those who already have hypertension include decreasing alcohol consumption or using another nonpharmacologic method to reduce hypertension; commencing, continuing or intensifying antihypertensive medication; or taking no action and remaining at increased risk of cardiovascular disease. OUTCOMES: The health outcomes considered were changes in blood pressure and in morbidity and mortality rates. Because of insufficient evidence, no economic outcomes were considered. EVIDENCE: A MEDLINE search was conducted for the period 1966-1996 with the terms ethyl alcohol and hypertension. Other relevant evidence was obtained from the reference lists of articles identified, from the personal files of the authors and through contacts with experts. The articles were reviewed, classified according to study design, and graded according to the level of evidence. VALUES: A high value was placed on the avoidance of cardiovascular morbidity and premature death caused by untreated hypertension. BENEFITS, HARMS AND COSTS: A reduction in alcohol consumption from more than 2 standard drinks per day reduces the blood pressure of both hypertensive and normotensive people. The lowest overall mortality rates in observational studies were associated with drinking habits that were within these guidelines. Side effects and costs were not measured in any of the studies. RECOMMENDATIONS: (1) It is recommended that health care professionals determine how much alcohol their patients consume. (2) To reduce blood pressure in the population at large, it is recommended that alcohol consumption be in accordance with Canadian low-risk drinking guidelines (i.e., healthy adults who choose to drink should limit alcohol consumption to 2 or fewer standard drinks per day, with consumption not exceeding 14 standard drinks per week for men and 9 standard drinks per week for women). (3) Hypertensive patients should also be advised to limit alcohol consumption to the levels set out in the Canadian low-risk drinking guidelines. VALIDATION: These recommendations are similar to those of the World Hypertension League, the National High Blood Pressure Education Program Working Group on Primary Prevention of Hypertension and the previous recommendations of the Canadian Coalition for High Blood Pressure Prevention and Control and the Canadian Hypertension Society. They have not been clinically tested. The low-risk drinking guidelines are those of the Addiction Research Foundation of Ontario and the Canadian Centre on Substance Abuse. SPONSORS: The Canadian Hypertension Society, the Canadian Coalition for High Blood Pressure Prevention and Control, the Laboratory Centre for Disease Control at Health Canada, and the Heart and Stroke Foundation of Canada. The low-risk drinking guidelines have been endorsed by the College of Family Physicians of Canada and several provincial organizations.

Adult↗
PubMed1975

[The consumption of alcohol, drugs and the smoking habits of 4,082 healthy young Swiss men as evidenced by a random study].

By means of written questionnaires and (with every third or fourth subject, selected at random) standardized interviews, 4082 recruits from various regions of Switzerland were asked about their alcohol and drug consumption and smoking habits in civilian life. To estimate the consumption pattern during military training all recruits still available towards the end of military service (64.3 percent) were questioned again regarding intake of alcohol, tobacco and drugs during military service. The inquiry showed that in civilian life only 10.4 percent were alcohol abstainers, 39.8 percent were non-smokers and 77 percent had no drug experience. 8.6 percent reported a weekly alcohol consumption of more than 350 g alcohol 100 percent (an amount corresponding to 9 1 beer, 41/2 1 wine, 1 1 brandy), 17.4 percent had smoked more than 24 g tobacco per day (corresponding to more than 24 cigarettes daily), and 10.6 percent had taken drugs more than 6 times in their lives. The study was also designed to demonstrate the relations between family or socioeconomic data and intake of alcohol, tobacco and drugs. It was found that French and Italian speaking recruits indicated a higher alcohol consumption, that the lower socioeconomic class was exposed to be greater risk with regard to alcohol and tobacco consumption and the separately interviewed group of pupils to the greatest risk of drug experinece. Sons of divorced or separated parents, of parents married after the subject's birth or of parents who are heavy alcohol, tobacco or medicament consumers represent a higher percentage among the highest consumption class for alcohol, tobacco and drugs than subjects who had grown up in stable families or whose parents had been non-consumers or only moderate consumers of alcohol, tobacco or drugs. Finally, a correlation was also found between use of leisure time and alcohol, tobacco and drug consumption. It was in the groups of recruits who spent their spare time rather passively that the highest percentage of subjects in the upper consumption classes for alcohol, tobacco and drugs was observed. During military training consumption patterns withregard to alcohol and tobacco hardly changed, and only a small number of subjects (7.7 percent of 2587) took drugs during this time.

Adult↗
PubMedDate not supplied

[Intersex and interspecies differences in sucrose consumption by rats with various behavioral strategies].

Sucrose consumption by male and female rats during active avoidance acquisition was measured in two rat strains: KLA (Koltushi low avoidance) and KHA (Koltushi high avoidance) selected for divergent performance in a shuttlebox. Under resting condition, there were no interstrain difference in sucrose consumption by males, but KHA females consumed significantly less sucrose than KLA females. Active avoidance acquisition during five consecutive days decreased sucrose consumption in KLA males and did not change sucrose consumption in KHA males. Within a week after exposure to the stress, the sucrose consumption by KLA males returned to its normal values, and KHA males consumed significantly more sucrose. The active avoidance conditioning did not affect sucrose consumption in females of both strains. Substitution of 32% solution for 4% produced on the first day a sharp decrease in sucrose consumption in males of both strains, while females sharply increased consumption of the diluted solution over the next four days of observation. During this time, males returned to consumption of the same volume of the solution despite its decreased concentration. The findings suggest that the exposure to the escapable stress induces the negative affect only in KLA males.

Adaptation, Psychological↗
PubMed2002

Decreased ethanol preference and consumption in dopamine transporter female knock-out mice.

BACKGROUND: It is commonly believed that the mesolimbic dopamine (DA) system participates in the etiology of alcoholism. One of the most important regulators of DA synaptic transmission is the DA transporter (DAT). We examined the effects of the genetic reduction or deletion of DAT on voluntary ethanol consumption and ethanol-induced sedation. METHODS: Ethanol preference and consumption were assessed in the two-bottle choice paradigm, and the depressant effects of ethanol were evaluated by measuring sleep time after acute injection of ethanol. RESULTS: The latent period to lose the righting reflex was shorter in both knock-out mice (DAT-KO) and heterozygote mice (HET) than in wild-type (WT) mice. No significant difference was found among the three genotypes in the ethanol blood concentration at the onset of regaining the righting reflex. Females of all genotypes consumed more fluid than males of the same genotype. HET and DAT-KO females had increased total fluid consumption compared with WT females. DAT-KO males had increased fluid consumption compared with WT and HET males. Ethanol preference and consumption were not different among male mice of different genotypes. WT and HET females demonstrated significantly higher ethanol consumption than males. HET female mice did not differ from WT mice in ethanol preference. There was no difference between HET and WT mice in the preference for saccharin or quinine solutions. DAT-KO females avoided ethanol, and their consumption and preference were lower than in WT and HET females, despite markedly increased total intake. DAT-KO mice also demonstrated altered taste preference for saccharin and quinine. CONCLUSIONS: Partial deletion of DAT results in increased fluid consumption in female mice but does not change ethanol preference in either sex. Complete deletion of DAT reduces ethanol preference in female mice; this may be due to a combination of the pharmacological actions of DAT deletion and alterations in fluid consumption and taste discrimination.

Alcohol Drinking↗
PubMedDate not supplied

[Evolution of antipsychotic drug consumption in the autonomous community of Castile and Leon, Spain (1990-2001)].

BACKGROUND: Over the past ten years, new drugs and new approaches to treatment have been implemented making it possible to assume changes in the use of antipsychotic drugs in our environment. This study is aimed at characterizing the pattern of use of antipsychotic drugs in Castile and Leon throughout the 1990-2001 period as well as ascertaining the bearing which the marketing of new antipsychotic drugs may have had on the pattern of consumption of these drugs. METHODS: The drug consumption data was obtained from the Ministry of Health and Consumer Affairs' consumption database ECOM (Especialidades Consumo de Medicamentos). This database contains information on the consumption of medications dispensed charged to the Social Insurance system in community pharmacies nationwide. To estimate the consumption outside of the National Health System, data from the IMS (International Marketing Services) firm for the years 2000 and 2001 was used. The data was given in Defined Daily Doses/1000 inhabitants/day. RESULTS: The use of antipsychotic drugs rose by 146% within the 1990-2001 period. Throughout the period studied, haloperidol was the antipsychotic drug most used in Spain and in Castile and Leon. The atypical antipsychotic drugs totaled 49% of the total consumption for 2001 and 90% of the costs, a strong trend being found toward an increase in the consumption of these atypical antipsychotic drugs in detriment to the typical antipsychotic drugs. It has been estimated that 14% of the antipsychotic drugs used in Castile and Leon were used outside of the National Health System.. Appreciable differences exist among the different provinces. CONCLUSIONS: The consumption of antipsychotic drugs in Castile and Leon grew by 146% throughout the twelve months studied. The marketing of new atypical antipsychotic drugs and the legal measures related to the deinstitutionalization of mental patients may have played a major role in this increase. The marketing of the new antipsychotic drugs has led to a change in their pattern of use and has give rise to an rise in the direct costs. The consumption of these medications not charged to the National Health System is minor, but not negligible.

Antipsychotic Agents↗
PubMedDate not supplied

[Consumption and cost of antipsychotic drugs].

INTRODUCTION: In recent years, new atypical antipsychotic drugs have been marketed. This study aims to analyze the evolution of the consumption pattern and pharmaceutical cost of the antipsychotic drugs during the last years and the impact that the new atypical antipsychotic drugs have had. METHODS: Based on the ECOM database of the Ministry of Health and Consumer Affairs of Spain, the sales data of the antipsychotic drugs in Catalonia during the 1990-2001 period have been chosen. The drugs have been classified into typical or classical and atypical. Consumption data have been expressed in daily defined dose (DDD) per 1,000 inhabitants and per day of treatment (DID), and cost data in constant euros. RESULTS: Antipsychotic consumption increased from 3.31 DID in 1990 to 6.04 DID in 2001. Typical drugs consumption decreased (from 100 % consumption in 1990 to 46 % in 2001) and that of the atypical ones increased (from 1% consumption in the year 1993 to 54% in the year 2001). A change in the use pattern of different drugs is verified. In the year 1990, the most consumed drugs were flupenthixol (0.86 DID) and haloperidol (0.67 DID), and in the year 2001 olanzapine (1.69 DID) and risperidone (1.30 DID). The drugs with a greater increase in consumption were olanzapine, which multiplied its consumption five fold from 1997 to 2001 and risperidone, which multiplied it by 20 from 1994 to 2001. During the study period, the cost increased 13 times, above all due to increase in cost of atypical antipsychotics (from less than 1 % of the total cost in 1993 to 92 % of the total cost in 2001). The DDD cost of antipsychotics increased (6.48 euros in 1990 and 20.31 euros in 2001). However, that of the typical antipsychotics decreased (6.48 euros in 1990 and 4.62 euros in 2001) and that of the atypical ones increased (2.06 euros in 1993 and 15.69 euros in 2001). CONCLUSION: The marketing of the new atypical antipsychotic drugs has had an extraordinary impact on antipsychotic drug consumption and cost. The cost/effectiveness ratio of the new atypical antipsychotic drugs in the clinical practice should be evaluated to determine the economic resources aimed at costs of the different antipsychotic drugs.

Antipsychotic Agents↗
PubMed2000

Oxygen consumption and lactate release by the lung after cardiopulmonary bypass and during septic shock.

OBJECTIVE: We sought to determine whether a correlation exists between lung lactate release and lung oxygen consumption by studying adult intensive care patients, either after cardiopulmonary bypass (CPB) or with septic shock. METHODS: A prospective observational study of six post cardiopulmonary bypass patients and seven patients with septic shock was performed in an intensive care unit of a major teaching hospital. Pulmonary oxygen consumption was estimated by subtracting oxygen consumption calculated using the reverse Fick equation (V O2Fick) from that measured by indirect calorimetry (V O2meas). Pulmonary lactate release was derived from the difference between arterial and mixed-venous lactate, multiplied by cardiac output. RESULTS: Pulmonary oxygen consumption comprised a substantial component of total oxygen consumption (CPB-median: 20.6%; interquartile range (IQR): 15.4 - 27.3%; septic shock-median: 32.3%; IQR: -4.0 - 35.4%). Lung lactate release occurred both after CPB (median: 27.5 mmol/hr; IQR: 24.8-64.1 mmol/hr) and with septic shock (median: 55.4 mmol/hr; IQR: 24.3 - 217.6 mmol/hr). Although no correlation was found between lung lactate release and pulmonary oxygen consumption, lactate release correlated with V O2meas and V O2Fick in septic patients (p < 0.005). CONCLUSIONS: We conclude that lung oxygen consumption and lactate release are substantial in conditions associated with lung inflammation. Lactate release and lung oxygen consumption may not share a common pathogenesis, however there is an association between lung lactate release and systemic oxygen consumption in sepsis.

Journal Article↗
PubMedDate not supplied

[Alcohol consumption and alcohol-induced psychoses in Poland in the years 1956-1986].

The dependence between alcohol psychoses morbidity and the average alcohol consumption in Poland in the period of time from 1956 till 1986 was studied. Alcohol consumption in Poland between 1981 and 1986 was different than during all previous post-war period. Therefore, the analysis of dependence between alcohol psychoses morbidity and alcohol consumption was performed in 2 periods of time: 1956-1980 and 1981-1986. The frequency of the first hospitalization of men with alcohol psychoses for 100,000 of population was accepted as an alcohol psychoses morbidity factor. As an indicator of alcohol consumption the average consumption of all kind of alcohol beverages in conversion to pure alcohol per capita per year was accepted. During the years 1956-1980 such dependence was demonstrated as a square function: y = .3 X2, with the correlation coefficient r = .99, where X designates the average alcohol consumption per person per year. and y denotes the morbidity with alcohol psychoses. During the years 1981-1986 the decline of such dependence was observed (r = .65). In 1981 there was rapid decrease of alcohol consumption; such decrease intensified slightly in 1982. This went with deep decline of alcohol psychoses morbidity. In the years 1983-1985 rapid increase of alcohol psychoses morbidity incomparable with a slight increase of alcohol consumption was found. In 1986 small alcohol consumption was accompanied with inconsiderable fall of morbidity.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcohol Drinking↗
PubMed1994

[Determinants of medical consumption in older subjects covered by national health insurance].

OBJECTIVE: Investigating to what extent the medical consumption of persons aged 50-80 yr covered by the Dutch National Health Service is explained by their health condition and sociodemographic factors like age, gender, marital status and education. DESIGN: Questionnaire. SETTING: 15 general practices (3 in each of 5 municipalities) in the provinces Drenthe and Overijssel, the Netherlands. METHOD: A one-time prestructured health questionnaire (in writing) was sent to 1875 persons aged 50-80 yr covered by the Dutch National Health Service (125 randomly selected persons from each practice). The response was 55% (n = 1022). The objective and subjective health conditions and the sociodemographic factors were tested in relation to the medical consumption (visiting a general practitioner, a specialist, or hospitalization) with a type of regression analysis with which both direct and indirect relations with medical consumption could be calculated. RESULTS: The medical consumption was explained for 17% by the health condition, the age and the level of education of patients. Elderly, single women with little education had the highest medical consumption. This was mainly determined by the higher probability of health problems in this group. Apart from this there was an age-related increase in medical consumption. CONCLUSION: Only part of the medical consumption can be explained by the main literature determinants of medical consumption. Refinement in research can be achieved by relating the care demand to research into referral behaviour of general practitioners and specialists, which can result in supplementary knowledge on determinants of medical consumption.

Age Factors↗
PubMed1993

[Alcohol consumption in a Danish cohort study over a period of 11 years].

A cohort living in Copenhagen County, originally consisting of 1198 persons, 577 men and 621 women, who were 40 years old in 1976, was reexamined in 1981 and again in 1987, 1052 (88%) participated in 1976, 922 (84%) in 1981, and 965 (85%) in 1987. The purpose of this study was to describe alcohol consumption changes in the cohort, with a view to identifying subgroups who significantly change their alcohol consumption behaviour. The same questionnaire was employed all three times to measure the alcohol consumption level and frequency. Alcohol consumption peaked in 1981 (45-years old) with 10.4 drinks on average a week. Men increased 8% and women 37%. There is an overall downward tendency in the consumption frequency among men whereas the opposite is the case among women. The two groups are converging toward a weekly consumption level. It seems now that the women are leading the change in the content of consumption with relatively more wine consumption. Therefore it is concluded that female consumption should be considered a target in future preventive programs.

Adult↗
PubMed1997

Effects of legume consumption on serum cholesterol, biliary lipids, and sterol metabolism in humans.

Legume consumption appears to lower serum cholesterol and to increase cholesterol saturation of bile, but the mechanisms of these effects have not been established. We studied nine human subjects on a metabolic ward during two randomly ordered 6-7 week periods: one during consumption of a control diet and the other during consumption of the same diet with 120 gm mixed legumes substituted for foods having equivalent calories, fat, protein, and carbohydrate. Mean serum LDL cholesterol was significantly lower during legume consumption (126 vs. 138 mg/dl, P = 0.039). Legume consumption significantly increased mean cholesterol saturation index of gallbladder bile from 1.07 to 1.26 (P = 0.016), largely because of an increase in hepatic secretion of cholesterol from a mean of 90.2 mumol/h to 100.8 mumol/h (P = 0.042). Fecal neutral sterol output was unaffected by legumes, but fecal acidic sterols increased from a mean of 861 to 1202 mumol/day (P = 0.002) during legume consumption. Mean sterol balance became significantly more negative during legume consumption (-2140 vs. -2700 mumol/day, P = 0.037) indicating an increase in cholesterol synthesis. Mean fractional absorption of bile acid was lower during legume consumption than (0.947 vs. 0.960, P = 0.003). These data suggest that legume consumption lower LDL cholesterol by partially interrupting the enterohepatic circulation of bile acids and increases cholesterol saturation of bile by increasing hepatic secretion of cholesterol.

Adult↗
PubMed1984

In situ oxygen consumption rates of cells in V-79 multicellular spheroids during growth.

The rate of consumption of oxygen by V-79 cells in multicellular spheroids was measured as a function of the spheroid diameter. In situ consumption was equal to that of exponentially growing cells for spheroids less than 200 micron in diameter. The rate of oxygen consumption decreased for cells in spheroids between 200 and 400 micron diameter to a value one-fourth the initial, then remained constant with further spheroid growth. Comparison of consumption rates for spheroid-derived cells before and after dissociation from the spheroid structure indicated that the spheroid microenvironment accounted for only 20% of the change in oxygen consumption rate. Cell-cell contact, cell packing, and cell volume were not critical parameters. Plateau-phase cells had a fivefold lower rate of oxygen consumption than exponential cells, and it is postulated that the spheroid quiescent cell population accounts for a large part of the intrinsic alteration in oxygen consumption of cells in spheroids. Some other mechanism must be involved in the regulation of cellular oxygen consumption in V-79 spheroids to account for the remainder of the reduction observed in this system.

Animals↗
PubMed1989

Maximum rate of oxygen consumption and quantitative histochemistry of succinate dehydrogenase in single muscle fibres of Xenopus laevis.

Three different types of single living muscle fibre were dissected from the iliofibularis muscle of Xenopus laevis. The fibres were mounted in a glass chamber and their rate of oxygen consumption was determined as a function of twitch frequency at 20 degrees C. The rate of oxygen consumption increased with twitch frequency until it levelled off and reached a maximum. The maximum rate of oxygen consumption varied between fibres (0.019 to 0.161 nmol O2 s-1 mm-3) and was reached at different twitch frequencies (less than 0.2 to 5.7 stimuli s-1). After the determination of the maximum rate of oxygen consumption, the succinate dehydrogenase activity in cross sections of the fibre was determined by means of a quantitative histochemical method. A proportional relationship between the maximum rate of oxygen consumption and the succinate dehydrogenase activity was found. The maximum rate of oxygen consumption and the succinate dehydrogenase activity are also proportional to the volume density of mitochondria in the three fibre types reported by Smith and Ovalle (1973; J. Anat., Lond. 116, 1-24). It is concluded that quantitative histochemistry of succinate dehydrogenase reliably predicts the maximum rate of oxygen consumption of muscle fibres in Xenopus laevis and that the maximum rate of oxygen consumption of single muscle fibres is determined by the volume density of mitochondria.

Animals↗
PubMedDate not supplied

The oxygen consumption paradox of "stunned myocardium" in dogs.

The contractile state of the heart is a major determinant of myocardial oxygen consumption. Since regional myocardial contractility can be severely impaired following a transient coronary occlusion, post-ischemic myocardium is frequently assumed to consume less oxygen. To test this assumption, regional myocardial function and oxygen consumption were studied in anesthetized dogs during 2 h of myocardial reperfusion following either a 15-min (Group I) or 4-h (Group II) left anterior descending coronary artery occlusion. Both groups developed similar post-ischemic regional dysfunction characterized by paradoxical motion (negative shortening). Measured as a percent of baseline segment shortening, anterior wall function in Group I (n = 8) and Group II (n = 5) at 30 min of reperfusion was -33 +/- 11% and -34 +/- 16% (p = NS) and at 120 min was -23 +/- 9% and -40 +/- 16% (p = NS). However, the two groups showed a marked difference in regional myocardial oxygen consumption during reperfusion. Despite the abnormal wall motion, regional oxygen consumption in Group I at 30 and 120 min of reperfusion was unchanged from pre-ischemic levels as measured as a percent of baseline: 104 +/- 20% (p = NS) and 111 +/- 21% (p = NS). In contrast, regional oxygen consumption in Group II was markedly depressed from baseline at 30 and 120 min of reperfusion: 42 +/- 7% (p less than .01) and 40 +/- 8% (p less than .01). To determine whether the dissociation between regional myocardial oxygen consumption and function in Group I was related to mitochondrial uncoupling, six additional dogs were studied. Tissue samples were obtained from post-ischemic myocardium after 120 min of reperfusion following a 15-min coronary artery occlusion, and compared to non-ischemic myocardium. There were no differences in the in vitro mitochondrial respiratory rates or oxidative phosphorylation capacity between the post-ischemic and non-ischemic myocardium. Therefore, in the post-ischemic myocardium, significant depressions in regional contractility may not be associated with falls in oxygen consumption. Following a 15-min coronary artery occlusion, the injured myocardium maintains a paradoxically high oxygen consumption with normal mitochondrial function despite decreased contractility and abnormal wall motion.

Animals↗
PubMed1989

The effects of substrate utilization, manipulated by caffeine, on post-exercise oxygen consumption in untrained female subjects.

The effect of substrate utilization manipulated by caffeine on post-exercise oxygen consumption was investigated in five untrained females (age = 21 +/- 1.5 years), following 90 min of treadmill walking at 55% maximal oxygen consumption. Each subject participated in the two trials (control and experimental) within 2 weeks of each other. Immediately following the measurement of resting oxygen consumption, subjects consumed one of the two test beverages 60 min prior to exercise: 5 mg of caffeine per kg of body-weight in 200 ml of orange juice (CA) or 200 ml of orange juice (C). Assignment of CA and C was made in a random, double blind fashion. Immediately prior to the exercise phase (0 min) resting oxygen consumption was again measured. Following exercise, subjects returned to the same pre-exercise sitting position where respiratory data was collected over 1 h. No significant differences were found in resting oxygen consumption and respiratory exchange ratio (R) prior to caffeine ingestion (-60 min). One hour after caffeine ingestion (0 min) oxygen consumption and free fatty acid (FFA) levels increased significantly compared to C. During and 1 h following exercise, oxygen consumption and FFA levels were significantly greater, with R values being significantly lower in CA compared to C. These findings provide further evidence that metabolic substrate is somehow implicated in elevating oxygen consumption following exercise cessation.

Adult↗
PubMed2002

Effects of inhibition of neuronal nitric oxide synthase on NMDA-induced changes in cerebral blood flow and oxygen consumption.

This study was performed to determine whether neuronal nitric oxide synthase (nNOS) is involved in altering regional cerebral blood flow (rCBF) and oxygen consumption during N-methyl- D-aspartate (NMDA) receptor stimulation. A craniotomy was performed in rats, under isoflurane anesthesia, to expose the cerebral cortex. For the control group (n=7), an NMDA patch (10(-3) M) was applied to the exposed cortex (ipsilateral cortex, IC) for 10 min before determining rCBF and O(2) consumption. The patch was changed every 5 min. To block nNOS, 7-nitroindazole (7-NI, 25 mg/kg i.p.) was administered 30 min before NMDA application (7-NI group, n=7). The autoradiographic technique was used to determine rCBF and regional O(2) consumption was measured using cryomicrospectrophotometry. Blood pressure, heart rate, blood gases, and hemoglobin were similar between the two groups. In the control group, rCBF (108+/-32 ml/100 g per min) and O(2) consumption (4.8+/-0.8 ml O(2)/100 g per min) of the IC where NMDA was applied were higher than those of the contralateral cortex (CC) (78+/-16 ml/100 g per min and 3.1+/-0.4 ml O(2)/100 g per min, respectively). Neither rCBF nor O(2) consumption of the IC of the 7-NI group was statistically different from that of the CC. However, O(2) consumption of the IC of the 7-NI group was lower (3.9+/-1.0 ml O(2)/100 g per min) than that of the IC of the control group. Our data demonstrated that a direct cortical application of NMDA increased O(2) consumption and rCBF, and that pretreatment with 7-NI not only attenuated the effects of NMDA on rCBF but also decreased the O(2) consumption during NMDA receptor stimulation.

Animals↗
PubMed1991

Inotropic stimulation and oxygen consumption in a canine model of dilated cardiomyopathy.

Inotropic support for the dilated, failing ventricle results in complex hemodynamic changes affecting preload, afterload, contractility, and heart rate, each of which affects myocardial oxygen consumption. Appreciation of a hierarchy of hemodynamic determinants of myocardial oxygen consumption may be helpful to the clinician trying to balance oxygen demands and hemodynamic performance. We tested the hypothesis that epinephrine alters the hierarchy of hemodynamic determinants of myocardial oxygen consumption in a canine model of dilated cardiomyopathy created by rapid ventricular pacing. Dogs (n = 10) were instrumented to record left ventricular pressure and dimension, and a modified right heart bypass preparation was used to control left ventricular workload. Coronary sinus effluent was quantitatively collected and analyzed for oxygen content and used to calculate myocardial oxygen consumption. Epinephrine administration significantly increased myocardial oxygen consumption in the empty, beating heart; however, when the relationships of multiple determinants of left ventricular work and load were compared before and after epinephrine administration, no oxygen wasting effect was observed. Using multivariate linear regression analysis, a hierarchy of hemodynamic determinants of myocardial oxygen consumption was created. In the untreated heart, stroke work and cardiac output were the primary hemodynamic determinants of oxygen consumption; epinephrine significantly altered the determinants such that wall stress became the dominant hemodynamic determinant of myocardial oxygen consumption. Focused manipulation of wall stress in the treated, failing heart may limit the potentially deleterious effects of inotropic stimulation in this setting.

Adenine Nucleotides↗