Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “FASTING”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,387 records · Page 77Linked to original sources
PubMed1988

Effect of fasting on aggregation of hepatocyte rough endoplasmic reticulum in adrenalectomized and 3'MeDAB-treated rats: quantitative electron microscope study.

A method for the quantitative analysis of the degree to which hepatocyte rough endoplasmic reticulum (ER) is arranged into parallel arrays was used to study the effect of fasting on rough ER aggregation in rat liver cells following either bilateral adrenalectomy or administration of the carcinogenic azo dye 3'-methyl-4-dimethylaminoazobenzene (3'MeDAB). One group of male inbred Leeds strain rats was subjected to bilateral adrenalectomy (ADX): after 1 week half of the animals were fasted for 24 h whereupon the whole group was killed. A second group of rats, fed for 4 weeks on a diet containing 0.06% of the carcinogenic azo dye 3'MeDAB, was similarly divided into two groups that were killed either with or without a prior 24-h fast. Untreated control groups of rats, both fasted and unfasted, were also killed. A quantitative electron microscope study was carried out to investigate the effect of each treatment on the degree to which the hepatocyte rough ER was aggregated into parallel arrays. ADX alone was without effect but caused a dramatic fall in rough ER aggregation when combined with fasting. At least as great an effect was induced by 3'MeDAB, with or without fasting, while fasting alone had a significant but much more modest effect than either ADX or the carcinogen. Thus, two disparate treatments induced morphologically identical responses in hepatocyte rough ER. The implications of this are discussed in terms of known interrelations between glucocorticoids and chemical carcinogenesis in the rat liver.

Adrenalectomy↗
PubMedDate not supplied

Mental alertness in response to hypoglycaemia in normal man: the effect of 12 hours and 72 hours of fasting.

To study the influence of hypoglycaemia and starvation on mental functions eight healthy male students age 25-34 years with an ideal body mass of 99.9% +/- 2.5% (mean +/- SEM) were recruited. Hypoglycaemia was induced in random order by an insulin-glucose clamp technique (insulin: 2.4 mU/kg/min + glucose at variable rate) keeping the venous blood glucose at 2.2 mmol/l both after an overnight fast and after 72 h fasting. Mental alertness was assessed by measuring the recognition time, moving time and total reaction time to a visual signal and by a verbal mental clearness test and a synonym learning test during normo- as well as hypoglycaemia. Hypoglycaemia prolonged the total reaction time (p less than 0.05) and the time required for the mental clearness test (p less than 0.05). Compared with a control study performed at normoglycaemia the learning effect of the synonym test was reduced by hypoglycaemia. Fasting, which resulted in a body weight reduction of 2.6 +/- 0.3 kg and ketonuria prolonged the total reaction time (p less than 0.005) by increasing the moving time but did not affect the mental clearness test. When hypoglycaemia was preceded by 72 h fasting it did not increase the total reaction time, nor did it modify the mental clearness test. Moreover, the learning effect of the synonym test was less impaired. In conclusion, mental alertness was reduced by moderate hypoglycaemia after an overnight fast while similar hypoglycaemia did not reduce mental alertness after prolonged fasting. This may illustrate a decrease of the glucose dependency of the central nervous system during prolonged fasting.

Adult↗
PubMed1988

Discrepancy of fasting plasma glucagon levels measured by different glucagon antisera.

To investigate the possible discrepancy between immunoreactive glucagon (IRG) levels measured by two glucagon-specific antisera, OAL-123 and 30K, fasting plasma IRG levels were measured in 30 diabetics (DM group), 56 patients with impaired glucose tolerance (IGT group) and 96 normal subjects (normal group). The fasting plasma IRG measured by OAL-123 (OAL-IRG) in DM, IGT and normal groups were 121 +/- 53, 125 +/- 43 and 119 +/- 57 pg/ml, whereas the fasting plasma IRG measured by 30K (30K-IRG) were 109 +/- 92, 92 +/- 44 and 91 +/- 68 pg/ml, respectively. There was no significant difference in the distribution of the fasting IRG levels among DM, IGT and normal groups. Although there was a statistically significant correlation between OAL- and 30K-IRG, their correlation coefficient was as small as 0.29, and 31 of 182 cases showed a large discrepancy exceeding 100 pg/ml between the two IRG values. The OAL- and 30K-IRG measured again six months later did not show a significant change, where the first and second IRG levels showed a good correlation (0.72 and 0.83 for OAL- and 30K-IRG, both p less than 0.001). The gel chromatography of the 14 plasma with fasting OAL-IRG higher than 200 pg/ml showed that the main contributor to the fasting IRG was the component of big plasma glucagon (BPG). These data suggest that there is a significant discrepancy in the fasting plasma IRG levels measured by the different glucagon antisera and that the discrepancy is caused by the different immunoreactivity of BPG to the different glucagon antisera.

Blood Glucose↗
PubMed1987

Nitrogen flux across ovine maternal and fetal hindquarters during fasting.

Nitrogen flux across the hindquarters of fetal and maternal sheep (n = 15) was determined during normal feeding and following 5 days of maternal fasting. Arterial and venous whole blood concentrations of free amino acids, ammonia and oxygen were measured entering and exiting the hindquarters. Further, the DNA, protein and nitrogen contents of the hindlimb skeletal muscle of the fetus were determined in the fed state and following the 5-day fast. Results of these studies indicate that maternal and fetal hindlimb metabolism differ during fasting. There is a net efflux of alanine, glutamine and total nitrogen from the maternal hindquarters following 5 days of fasting. The fetus also releases glutamine and alanine from the hindquarters during the fast, presumably as potential energy substrate. However, nitrogen balance across the fetal hindquarter remains positive as a result of increased positive arteriovenous differences for other amino acids (particularly leucine and isoleucine). The concentrations of DNA, protein and nitrogen in fetal skeletal muscle remain unchanged during fasting. These data indicate that, whereas the mother undergoes protein catabolism and net nitrogen loss from the hindquarter during fasting, the fetus maintains a positive nitrogen balance across the hindquarter.

Amino Acids↗
PubMed1985

Intrahepatic assembly of very low density lipoproteins. Varied synthetic response of individual apolipoproteins to fasting.

Hepatocytes obtained from rats fed for 3 days chow (control) or drinking water only (fasted) were used to examine how metabolic state affects lipogenesis, apolipoprotein synthesis, and the capacity to secrete de novo synthesized triacylglycerol. The secretion of triacylglycerol (mass and 3H-labeled via 3H2O incorporation) by both groups of cells was constant for 30 h. Moreover, cells from fasted rats secreted triacylglycerol at rates which were markedly reduced (mass -84%; 3H-labeled -91%). To assess the relative capacities of the two groups of hepatocytes to augment triacylglycerol secretion in response to stimulated lipogenesis, cells were incubated with increasing concentrations of glucose. Control cells responded to glucose by increasing equally the synthesis and secretion of [3H] triacylglycerol. When cells from fasted rats were challenged with glucose, triacylglycerol secretion was not increased. Rather, it accumulated intracellularly. Double-reciprocal plot analysis of the capacity to augment triacylglycerol secretion in response to glucose showed that cells from fasted rats had a greater than 10-fold decrease in V'max. Moreover, fasting changed the synthesis and secretion of apolipoproteins selectively: secretion of low molecular weight apo-B was decreased 50%, large molecular weight apo-B was unchanged, and apo-E was increased 2-4-fold. Analysis of the lipoproteins from both groups of cells on Bio-Gel A-50m showed that the very low density lipoprotein secreted by cells from fasted rats was smaller. In addition, all of the increased de novo synthesized apo-E secreted by cells from fasted rats eluted after the triacylglycerol-rich lipoproteins. The combined data show that: 1) the synthesis of individual very low density lipoprotein apolipoproteins is independently regulated, and 2) the synthesis (availability) of apo-B determines the capacity of the hepatocyte to assemble/secrete triacylglycerol-rich very low density lipoprotein.

Animals↗
PubMed1985

Hepatobiliary transport of indocyanine green and sulfobromophthalein in fed and fasted horses.

Fasting is associated with unconjugated hyperbilirubinemia in several species, including the horse. Studies in ponies showed that a 3-day fast decreased plasma clearance of bilirubin, cholic acid, and sulfobromophthalein (BSP). Since these organic anions are conjugated with different substrates, it is possible that observed differences in plasma clearance result from a general decrease in hepatic conjugating capacity during the animals' fasting. To test this hypothesis, the effects of a 3-day fast on plasma clearance of IV injected BSP (4.4 to 5.1 mg/kg), which is conjugated to glutathione, and indocyanine green (ICG; 0.8 to 1.1 mg/kg), which is not conjugated, were studied in 10 healthy horses and 2 ponies with diverted enterohepatic circulations (indwelling T tubes). Blood samples were obtained for 30 minutes after injection, and bile samples from ponies were obtained for 3 hours. Fasting increased plasma bilirubin concentration in all animals studied (from 1.03 +/- 0.337 mg/dl in control animals to 3.49 +/- 1.01 mg/dl in fasted animals). Kinetic values of ICG disappearance were determined from single exponential functions, and those for BSP were determined from both single and curvilinear (2-exponential) functions. Plasma clearance of BSP in fed horses (8.65 +/- 1.02 ml X min-1 X kg-1) was greater than clearance of ICG (3.54 +/- 0.67 ml X min-1 X kg-1), results similar to those reported in dogs, cats, rats, and persons. Fasting significantly decreased fractional plasma disappearance rate of both BSP (-36%) and ICG (-58%) and similarly reduced plasma clearance (BSP,-48%; ICG,-55%).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

Effect of fasting on hypoxia tolerance of mice in relation to oxygen consumption and heart rate.

Mice more than 8 weeks old were fasted for 1 or 2 d and challenged by severe acute hypoxia. The hypoxia survival times (ST) were compared to the body weight, oxygen consumption (VO2), or heart rate (HR) of each animal. The duration of fasting was found to be important to determine ST. VO2 or HR were negatively correlated with ST, whether mice were fasted or not. The regression line (InST on HR) in the fed (control) group did not significantly differ from that of 2-d fasted groups, but those of fed and 1-d fasted groups differed. These results suggested that, in fasting for 2 d, the reduction in energy consumption was a major determining factor of hypoxia survival; in 1-d fasting, other factors might operate to determine the tolerance.

Animals↗
PubMed1985

Increased secretion of growth hormone in rats undergoing catch-up growth after fasting.

The pattern of pulsatile secretion of growth hormone (GH) was determined in catheterized undisturbed male Long-Evans rats which had been fasted for 48 hours beginning at 39 days of age and then fed a stock diet ad lib. Plasma GH was determined at 15 minute intervals for 6 and 24 hour periods at 12 to 26 days into recovery during which time catch-up growth is known to occur in this fasted rat model. Secretion in fasted-refed rats occurred in characteristic periodic bursts of pulses resulting in plasma values that tended to be above 200 ng/ml; the intervening troughs had values under one ng/ml. The mean period of secretory bursts ranged from 2.4 to 3.1 hours in different groups and in light and dark periods; periods did not differ significantly by t test between fasted-refed and control rats. In fasted-refed rats sampled for 24 hours the area under the curve of GH concentration plotted against tie was significantly greater in light than in dark; this difference did not occur in controls. In rats sampled for 6 hours in light the area under the curve of GH concentration was significantly greater in the fasted-refed rats than in the controls. The findings show that the GH secretion in rats is increased in the light phase of the diurnal light/dark cycle during catch-up growth after fasting; the increased secretion occurs within the normal periodic pattern of GH secretion. We conclude that GH secretion is linked to the catch-up phenomenon but that the role of GH in catch-up growth remains unclear.

Animals↗
PubMed1983

High-affinity nitrosamine dealkylase system in rat liver microsomes and its induction by fasting.

In order to elucidate the enzymic basis of nitrosamine metabolism, the in vitro metabolism of nitrosamines by rat liver microsomes and the effects of fasting on the microsomal enzymes have been studied. Fasting for 1 to 3 days causes a 2- to 3-fold enhancement of the reduced nicotinamide adenine dinucleotide phosphate-dependent nitrosodimethylamine demethylase (NDMAD) activity. The cytochrome P-450 content and the activities of reduced nicotinamide adenine dinucleotide phosphate-cytochrome P-450 reductase and benzphetamine demethylase, however, are only modestly increased. Gel electrophoretic analysis reveals the induction of a 50,000-dalton protein band during fasting. The induction of this protein band as well as the enhancement of NDMAD activity are inhibited by CoCl2 and inhibitors of protein and RNA biosynthesis. The involvement of cytochrome P-450 in the NDMAD is supported by the fact that microsomal reduced nicotinamide adenine dinucleotide phosphate-cytochrome P-450 reductase is required for the demethylase activity. Kinetic analysis indicates that a low-Km form of NDMAD (apparent Km, 0.07 mM) is markedly induced by fasting. With microsomes of control rats, there are at least three apparent Km values (0.07, 0.38, and 38.6 mM) for NDMAD; but with microsomes of fasting rats, the low-Km (0.07 mM) form is predominant. These results suggest that rat liver microsomes contain a cytochrome P-450 isozyme which has high affinity for nitrosodimethylamine, and this isozyme is induced by fasting. In addition to nitrosodimethylamine, the oxidative demethylation of N-nitroso-N-methylethylamine, N-nitroso-N-methylbutylamine, N-nitroso-N-methylaniline, and N-nitroso-N-methylbenzylamine is also enhanced by fasting. The extent of enhancement and substrate dependency of these reactions, however, is different from that of NDMAD.

Animals↗
PubMed1983

Metabolic consequences of fasting during Ramadan in pregnant and lactating women.

In studies in a rural West African village it was observed that all lactating women and 90 per cent of pregnant women fasted throughout the period of Ramadan. The metabolic consequences of this fasting were studied by measuring serum glucose, free fatty acid, triglyceride, beta-hydroxybutyrate, alanine, insulin, glucagon and T3 levels at 0700 h and 1900 h in 22 pregnant, 10 lactating and 10 non-pregnant, non-lactating women. Results were also compared with overnight-fasted values obtained outside Ramadan. Values for the lactating women were not significantly different from the non-pregnant, non-lactating controls despite the additional metabolic stress of lactation. Ramadan-fasted (1900 h) glucose values from women in late pregnancy (3.01 +/- 0.11 mmol/l) were significantly lower than all other groups (P less than 0.01) and were 15 per cent (P less than 0.01) lower than overnight-fasted values from similar subjects. Ramadan-fasted free fatty acid and beta-hydroxybutyrate levels were significantly higher (P less than 0.05) and alanine values were significantly lower (P less than 0.05) in late than in early pregnancy. It is concluded that the phenomenon of 'accelerated starvation' occurs when women in late pregnancy fast during Ramadan. The possible consequences of this failure to maintain glucose homoeostasis are discussed with reference to the poor outcome of the actual pregnancies studied.

3-Hydroxybutyric Acid↗
PubMed1983

Ketone body, glucose, lactic acid, and amino acid utilization by tumors in vivo in fasted rats.

Arteriovenous differences for acetoacetate, beta-hydroxybutyrate, glucose, lactic acid, and glutamine and other amino acids were measured across Morris hepatomas 5123C, 7777, and 7288CTCF and Walker sarcocarcinoma 256 in vivo in rats fasted for 2 days. The acetoacetate and beta-hydroxybutyrate concentrations in arterial whole blood of fasted tumor-bearing rats were 0.52 +/- 0.06 and 1.82 +/- 0.19 mM (S.E., n = 38), respectively. Both ketone bodies were utilized by the tumors, and the rates of utilization were directly related to the rates of supply. The mean utilization rates for acetoacetate and beta-hydroxybutyrate were 13.9 +/- 2.9 (range, 0 to 64; n = 30) and 24.7 +/- 4.4 (range, 0 to 145; n = 38) nmol/min/g tumor wet weight, respectively. Eight of the tumors produced acetoacetate, presumably from utilized beta-hydroxybutyrate. An average of 52% of the acetoacetate and 30% of the beta-hydroxybutyrate carried in the arterial blood was removed during one pass through the tumors. The concentrations of glucose and glutamine in the arterial whole blood of fasted tumor-bearing rats (n = 38) were 6.55 +/- 0.3 and 0.76 +/- 0.02 mM, respectively; both of these substrates were utilized at rates that were directly proportional to the rates of supply. The mean rates of glucose and glutamine utilization for all tumors in fasted rats were 101 +/- 11 (range, 3 to 313) and 8.2 +/- 1.1 (range, 0 to 25.1) nmol/min/g tumor wet weight, respectively. Thirty-six % of the glucose and 25% of the glutamine supplied to the tumors was utilized. Comparison (by linear regression and analysis of covariance) of the rates of supply and utilization of glucose and glutamine in tumors growing in fasted versus fed rats indicated that these substrates are utilized more efficiently by tumors growing in fasted animals. Lactic acid was either produced or utilized, depending on the arterial whole-blood concentration. Production or utilization occurred, respectively, when the arterial lactate concentration was less or greater than 1 to 3 mM. The arterial whole-blood amino acids (except glutamine) were utilized at rates that ranged from 1 to 4 nmol/min/g tumor wet weight. The results indicate that energy production for tumor growth in fasted rats is supported, in part, by an increased availability of ketone bodies, by an increased efficiency of utilization of glucose and glutamine, and, under certain circumstances, by utilization of lactic acid.

3-Hydroxybutyric Acid↗
PubMed1982

Effects of fasting and adrenalectomy on the kinetics of glucose metabolism in granivorous and carnivorous birds.

1. [1-(14)C]-Glucose was used to estimate the rate of glucose replacement and of hexose recycling via 3-carbon compounds in fed, fasted and fasted-adrenalectomized granivorous (chickens) and carnivorous (black vultures) birds. 2. Fed chickens had a larger body glucose mass and 3 to 4-fold higher rates of glucose replacement than fed black vultures. Glucose recycling represents a larger fraction of the overall glucose replacement rate in chickens (60%) than in black vultures (25%). 3. Following a 72-h fast, the body glucose mass of chickens decreased markedly, without appreciable changes in fractional turnover rates but glucose replacement rates were reduced to 48% of fed values. In contrast, these parameters were much less affected by fasting in carnivorous birds, the largest difference being the rate of replacement which was 70% of the fed values. 4. In both species, fasting after adrenalectomy induced a marked reduction of body glucose mass. However, while fractional turnover rates increased in black vultures, they actually decreased in chickens. Consequently, glucose replacement rates were markedly reduced in fasted-adrenalectomized chickens, but did not change or increase in black vultures. Adrenalectomized chickens showed decreased tolerance to intravenous glucose loads. 5. The results indicate that: a) the maintenance of constant blood sugar levels during prolonged fasting in carnivorous birds is due solely to their high gluconeogenic capacity and b) in carnivorous, but not granivorous birds, increased rates of peripheral glucose utilization plus diminished gluconeogenesis contribute to reduce blood sugar levels after adrenalectomy.

Adrenal Glands↗
PubMed1980

Sequential deiodination of thyroxine to 3,3'-diiodothyronine via 3,5,3'-triiodothyronine and 3,3',5'-triiodothyronine in rat liver homogenate. The effects of fasting versus glucose feeding.

The characteristics of thyroxine (T4) deiodination to 3,5,3'-triiodothyronine (T3) and 3,3',5'-triiodothyronine (rT3) and of each of the latter to 3,3'-diiodothyronine (3,3'T2) were examined in rat liver homogenate. Each of the four reactions was enzymatic in nature, demonstrating pH and temperature optima, and tissue and time dependence. All reactions were considerably augmented (greater than 10-fold) by the presence of a thiol agent. At pH 7.2 with 2 muM T4 as substrate, rT3 generation was 3.3 +/- 0.44 (S.E.) and T3 formation was 4.8 +/- 0.57 pmol/min/100 mg of homogenate protein. Fasting for 72 h resulted in a significant inhibition of T4 deiodination, compared to that in the glucose-fed animals, in a 2% homogenate preparation. Enzyme activity for T4 to T3 was reduced by 54% (p less than 0.05) in the homogenate from the fasted rats. Fasting lowered the enzyme activity of T4 to rT3 by 56% (p less than 0.05). Although the monodeiodination of T3 to 3,3'-T2 was also significantly depressed (p less than 0.01) by fasting, rT3 deiodination to 3,3'-T2 was not. The in vitro additon of 5 mM dithioerythritol did not reverse the effect of fasting on any reaction. These results demonstrate that a 72-h fast significantly impairs the sequential deiodination of T4 in liver homogenate. The effect of fasting appears to be mediated mainly through a reduction in enzyme concentration rather than co-factor availability.

Animals↗
PubMed1995

Biological variation and the effect of fasting and halothane anesthesia on plasma glutathione S-transferase concentrations.

Using a specific RIA, we have investigated in patients and volunteers whether fasting, diminished hepatic clearance, hemoconcentration, or within-day biological variation might be responsible for the transient increases in plasma glutathione S-transferase (GST) concentration observed after anesthesia. GST concentration was measured in 44 healthy volunteers after an overnight fast and at 3, 6, and 24 h after the fasting sample. The concentration was significantly lower at 3 and 6 h after than in the fasting sample (P = 0.0019 and P = 0.015, respectively). The change in GST concentration caused by fasting was examined in 30 subjects by comparing pre- and postfasting values. Fasting had no significant effect on GST concentration overall (P = 0.4721), but two individuals showed a marked increase in GST concentration after fasting overnight. In a separate study of 10 patients, plasma amylase activity and plasma concentrations of GST and albumin were measured immediately before and 3 h after induction of halothane anesthesia. Although GST concentration was increased at 3 h in each of the 10 patients, plasma amylase activity and plasma albumin concentration were significantly decreased in all patients (P = 0.002). Apparently, increases in GST concentration after anesthesia do not result from incidental factors.

Adult↗
PubMed1994

Effect of route of nutrition on recovery of hepatic organic anion clearance after fasting.

BACKGROUND: Previous work documented a 40% depression of hepatic indocyanine green (ICG) clearance (ClICG) in pigs fasted to 20% weight loss, with return to normal within 12 days of food refeeding. ClICG in pigs is insensitive to changes in hepatic blood flow but very sensitive to changes in hepatic function (HF). Serial ClICG determinations were performed to quantify the effect of route of nutrient delivery on recovery of HF. METHODS: Fourteen pigs were fasted to 20% weight loss (12.8 days average) with both gastrostomy and intravenous catheters placed in each animal midway through the fast. ClICG was measured before fast, after fast, and after 12 days refeeding through the enteral or parenteral route at 125 kcal/kg/day with isonitrogenous, isocaloric diets containing 9% fat. Urine and stool were analyzed for total nitrogen. RESULTS: No significant differences appeared between groups in nitrogen output during fasting (4.5 +/- 1.2 gm/kg enteral, 4.6 +/- 1.2 gm/kg parenteral), in nitrogen intake (800 +/- 19 mg/kg/day enteral, 810 +/- 10 mg/kg/day parenteral), or in before or after fast ClICG, but enteral feeding produced more positive nitrogen balance. ClICG improved significantly with enteral but not with parenteral feeding. CONCLUSIONS: Enteral feeding produces faster nitrogen accrual and reverses the depression of major pathways of bilirubin and organic anion excretion associated with malnutrition. Parenteral feeding failed to improve organic anion clearance despite weight gain.

Analysis of Variance↗
PubMed1993

Equine fasting hyperbilirubinemia.

It appears that different mechanisms responsible for fasting hyperbilirubinemia may be operative in different mammalian species (and subspecies). An increase in bilirubin production does not seem to occur in the horse, but a decrease in the hepatic uptake of bilirubin has been supported by a number of studies. Even though the delay in plasma elimination could also result from a decrease in hepatic blood flow, this possibility does not seem to play a major role since the hepatic uptake of compounds with low intrinsic hepatic clearance (e.g., ICG and bilirubin) appear to be affected more during fasting than those with higher clearances (e.g., BSP, bile acid, antipyrine, acetaminophen, and lidocaine) (Table I). Other possibilities such as a decrease in the affinity of hepatocellular membrane carriers involved in the uptake of these compounds or altered content of intracellular proteins involved in cellular transport or storage of bilirubin have not been investigated in horses. Competition with free fatty acids for these carrier-mediated events seems likely, particularly because horses and ponies experience high degrees of hyperlipidemia during fasting. However, studies that have explored the competition hypothesis, while not entirely negative, do not fully support it as being the sole mechanism responsible for this phenomenon. Hepatocellular UDPGT activities have not been adequately investigated in horses, but it is apparent that intraduodenal infusion of glucose is effective in reducing fasting hyperbilirubinemia and also in increasing biliary bilirubin excretion. It therefore seems possible that UDP-glucose and UDPGA levels in the livers of horses could be reduced during fasting, thus resulting in substrate depletion for the conjugating enzymes. As pointed out by Freedland et al. (1991), it is also possible that the horse, like the Bolivian squirrel monkey, might also have a relatively high apparent Km and low Vmax for UDPGT, thus resulting in high steady-state levels of plasma bilirubin, particularly during fasting. Although little is known about the cause of equine fasting hyperbilirubinemia and the subtle factors that may be modulating slight changes in the production, hepatocellular uptake, binding, conjugation, and/or biliary excretion of this pigment, it is known that it can be rapidly reversed by refeeding native hay. Perhaps one direction for future research could point toward more fully exploring what aspects of feeding are responsible for reversing this intriguing physiological phenomenon.

Animals↗
PubMed1993

[Analysis of the variations of clinical test data on fasting therapy using fuzzy similarity dendrogram].

The values of assayed various chemical constituents in serum were varied on fasting therapy. The correlationship of the change among such constituents was investigated by drowning the dendrogram using fuzzy similarity relations. Normal and severe obese subjects were respectively selected from the fasting patients at Hyogo prefectural KENKO DOJO, and in contrast non-fasting healthy people were also selected. Fasting was practice under the conditions of 300 Kcal per day for 7 days, and then refeeding was enforced for 7 days after fasting. 21 Items of biochemical tests were used for this analysis, and dendrogram was drown by Otake's method. On the dendrogram of reference, the significant correlations between AST and ALT, Total Protein and Cholinesterase, Sodium and Potassium were found. The dendrogram of fasting period of normal group showed the simple patterns, and unique correlations were drawn on the dendrogram of refeeding period of normal group. The dendrogram of severe obese group of refeeding period showed more simple patterns than fasting period.

Adolescent↗
PubMed1993

Association of fasting insulin with blood pressure in young individuals. The Bogalusa Heart Study.

BACKGROUND: The relationship between fasting plasma insulin and blood pressure was studied in a cross-sectional survey of children and young adults aged 5 to 26 years. METHODS: Fasting plasma insulin, glucose, blood pressure, and anthropometric measurements were obtained on 3518 individuals. RESULTS: When divided into four age groups, the analyses showed that fasting insulin was significantly and positively correlated to both systolic and diastolic blood pressure in individuals at all age groups, except at 13 to 17 years. In multivariate regression analyses, fasting insulin remained independently associated with blood pressure levels after controlling for glucose levels, body mass index (weight/height) and skinfold thickness in children (aged 5 to 12 years) and young adults (aged 18 to 26 years), although not in adolescents (aged 13 to 17 years). Moreover, fasting insulin was more strongly related to systolic than to diastolic blood pressure. The fasting blood glucose level did not contribute independently to multivariate prediction of blood pressure in young adults. When the children and young adults were divided into tertiles according to fasting insulin and body mass index, the independent effect of insulin and body mass index on systolic pressure was also seen in children and young adults. CONCLUSIONS: The association between plasma insulin and blood pressure noted even in healthy children and young adults help target areas for cardiovascular risk prevention.

Adolescent↗