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PubMed2003

Evaluation of mycelial inocula of edible Lactarius species for the production of Pinus pinaster and P. sylvestris mycorrhizal seedlings under greenhouse conditions.

Different methods to inoculate seedlings of Pinus pinaster and P. sylvestris with edible Lactarius species under standard greenhouse conditions were evaluated. Fungal inoculations were performed both under pure culture synthesis in vitro, followed by transplantation of acclimatized seedlings, and directly in the greenhouse using different techniques for inocula production (mycelial slurries, vegetative inoculum grown in peat-vermiculite and alginate-entrapped mycelium). In vitro inoculations with L. deliciosus produced thoroughly colonized seedlings. However, a sharp decrease in mycorrhizal colonization was detected on transplanted seedlings after 4 month's growth in the greenhouse. On the other hand, all the inocula applied directly in the greenhouse, except the alginate-entrapped mycelium, produced a variable number of mycorrhizal seedlings and colonization rates after the first growing season, depending on the plant-fungal combination and the inoculation method. Inoculations with vegetative inocula of the strain 178 of L. deliciosus were the most effective in producing mycorrhizal seedlings. All the seedlings inoculated with this strain were colonized although the colonization rates were relatively low. The commercial feasibility of the different inoculation methods for the production of seedlings colonized with edible Lactarius species is discussed.

Agaricales↗

PubMed2005

Effect of a swim training on homocysteine and cysteine levels in rats.

The purpose of this study was to investigate the effects of a 8-week of swim training on total plasma homocysteine and cysteine levels in 16 male Sprague-Dawley rats aged 17 weeks. We also evaluated the activity of hepatic cystathionine beta-synthase (CBS), an enzyme involved in the metabolism of Hcy, the concentration of plasma glutathione, taurine, and a fraction of vitamin B6: the pyridoxal 5-phosphate (PLP). After one week of acclimatization, rats were randomly divided into two groups: 8 non-trained (NTR) and 8 trained rats (TR). Following the training period, body weight gain was lower in TR than in NTR. Plasma homocysteine did not differ among groups while significantly lower plasma cysteine and taurine levels were found in TR (157.83 +/- 8.6 micromol/L; 133.01 +/- 9.32 micromol/L; P < 0.05) compared with data of NTR (176.19 +/- 4.9 micromol/L; 162.57 +/- 8.16 micromol/L; P < 0.05). No significant changes in hepatic CBS activity were observed in TR compared with NTR. Moreover, values for plasma glutathione and PLP concentrations were not affected by training.These results indicate that training reduces plasma cysteine and taurine levels whereas it does not modify other studied parameters. Thus, physical training may regulate cysteine metabolism.

Animals↗

PubMed2005

Osteoclast development in immobilized bone is suppressed by parathyroidectomy in mice.

We tested the hypothesis that signaling of parathyroid hormone (PTH) facilitates osteoclastogenesis in bone marrow cells after immobilization, thereby reducing trabecular bone volume. We performed histomorphometric analyses in immobilized limbs after right sciatic neurectomy (IM) and in the contralateral limbs after sham surgery (M). Mice underwent thyroparathyroidectomy (TPTX) and then 0.2 microg/body of thyroxine was given three times a week, or the mice were subjected to sham surgery (sham). Six-week-old male ddY mice were assigned to four groups, as follows, after acclimatization for 1 week: M + sham, IM + sham; M + TPTX, and IM + TPTX. Bilateral tibial samples were used for analysis. Trabecular bone volume (BV/TV) in the secondary spongiosa of the proximal tibias in IM + sham was significantly reduced compared to that in M + sham. Osteoclast surface (Oc.S/BS) and number (Oc.N/BS) in IM + sham transiently increased at 3 and 4 weeks after IM. In contrast, TPTX partially prevented the IM-related reduction of BV/TV and completely suppressed the transient increases of Oc.S/BS and Oc.N/BS. In the bone marrow cells, the mRNA expression of RANKL was elevated in IM + sham, but not in IM + TPTX, compared to that in M + sham. The percentage of Mac-1-positive bone marrow cells, osteoclast precursors, was not altered after IM. There were no significant differences in the concentrations of interleukin (IL)-1alpha in the tibial bone marrow cell culture medium between M + sham and IM + sham. Our data demonstrated that significant increases in osteoclast surface and number after IM were suppressed in TPTX mice, closely associated with a reduction in the high expression of RANKL mRNA in the tibial bone marrow cells. We speculate that enhanced osteoclastogenesis due to limb immobilization may be related to the elevation of RANKL expression by the facilitation of parathyroid hormone signaling in bone marrow cells.

Animals↗

PubMed2001

The 60-kDa heat shock protein (HSP60) of the sea anemone Anemonia viridis: a potential early warning system for environmental changes.

Expression of heat shock proteins (HSPs) is often correlated with adaptation to environmental stress. We examined the role of HSP60 (60 kDa) in acclimatization to thermal stress in the sea anemone Anemonia viridis. Using monoclonal antibodies, we identified HSP60 in sea anemones for the first time, and showed that its expression varied with changes in seawater temperature (SWT). Anemonia viridis displayed high levels of HSP60 when extreme temperatures prevailed in stressful habitats such as tidal pools. Specimens sampled from different temperature layers in the same tidal pool differed in their levels of HSP60. Specimens from subtidal zones exhibited a seasonal pattern of expression of HSP60, according to the seasonal SWT. The level of HSP60 was significantly higher in the summer (SWT, 31 degrees C) than in other seasons throughout the year. This study suggests the use of HSP60 expression as a tool for stress detection in marine invertebrates.

Journal Article↗

PubMed2026

Bioprospecting Chromobacterium violaceum for bioremediation: an alternative to environmental lead pollution.

Lead pollution is a major environmental concern, but current decontamination technologies remain limited due to high costs. Therefore, alternative biotechnological processes have been successfully developed and applied due to their reduced cost and lower aggressiveness in the environment. The remarkable adaptive versatility of Chromobacterium violaceum in metal-contaminated environments makes this bacterium a promising candidate for Pb bioremediation. Therefore, the reference strain C. violaceum ATCC 12,472 and the environmental isolate C. violaceum SCV1, the first strain of this species isolated from a Brazilian area with natural Pb occurrence, were evaluated for Pb resistance under different Pb concentrations and exposure times. Pb biosorption was assessed by scanning electron microscopy, while strain-specific protein profiles were characterized using tandem mass spectrometry-based proteomic analysis. The results obtained revealed the potential of C. violaceum to perform lead bioremediation. Scanning electron microscopy analysis confirmed the biosorption of lead by C. violaceum strains. C. violaceum SCV1 was able to remove up to 40% more lead concentration when compared to ATCC 12,472 which suggested adaptation through natural selection process of C. violaceum SCV1. Proteome analysis revealed 1531 proteins, of which several are candidates for lead bioremediation. This is the first study on the resistance proteomics of C. violaceum against lead. The acclimatization of the bacteria linked to the identification of several proteins related to: biosorption; efflux and ionic uptake (bioaccumulation); biomolecule transport; and biomethylation, point out to this organism as a potential lead bioremediation agent.

Chromobacterium↗

PubMed2007

Association between ventilatory response to hypercapnia and obstructive sleep apnea-hypopnea index in asymptomatic subjects.

The majority of awake ventilatory control studies have shown normal or decreased ventilatory response to hypercapnia (HCVR) in obstructive sleep apnea-hypopnea syndrome (OSAHS) patients. These findings are contrary to experimental studies suggesting increased loop gain and greater breathing instability in OSAHS patients. We have investigated the relationship between central chemoreflex sensitivity tested by HCVR and obstructive sleep apnea/hypopnea index (OSAHI) in asymptomatic subjects. Twenty normal volunteers (10 men and 10 women) from the general population without physical complaints including sleep-related symptoms were included. The subjects were studied for awake ventilatory responses to hypoxia (HVR) and hypercapnia. Overnight polysomnography (PSG) was performed in two consecutive nights with the first night used as acclimatization. The subjects have an average body mass index (BMI) of 27 +/- 5 SD kg/m(2), ages of 35 +/- 9 SD years and Epworth sleepiness scale of 2.1 +/- 1.8 SD. A positive linear relationship was found between HCVR and logarithmically transformed OSAHI (r = 0.67, p = 0.001). BMI and age were not significantly correlated to HCVR or Log OSAHI. No relationship was found between HVR and Log OSAHI (r = 0.25, p = 0.29). Percentage oxygen saturation nadir during sleep was found to significantly correlate to both daytime HCVR (r = -0.60, p = 0.005) and Log OSAHI (r = -0.65, p = 0.002) and tended to correlate to HVR (r = -0.41, p = 0.07). Arousal index during sleep was not associated with either HCVR (p = 0.93) or HVR (p = 0.26). In conclusion, heightened central chemosensitivity was positively related to OSAHI in asymptomatic volunteers. We believe these findings are in keeping with the evolving theory of loop gain being a significant factor for respiratory control instability and obstructive apnea genesis. The mechanism can be applied to asymptomatic subjects with even minimal sleep-disordered breathing.

Adult↗

PubMed2026

Development of an Efficient Regeneration and Agrobacterium-Mediated Transformation Protocol for Hosta 'Light Star' Using the RUBY Reporter Gene.

Hosta plantaginea is a perennial shade-tolerant herb of the Liliaceae family, with high ornamental and urban greening value. Hosta 'Light Star' is a newly developed ornamental cultivar with yellow-margined leaves and lilac flowers, but no efficient in vitro regeneration or genetic transformation system has been established for this cultivar to date. In this study, we established a highly efficient in vitro regeneration system for Hosta 'Light Star,' and developed an Agrobacterium-mediated genetic transformation protocol using the RUBY visual reporter gene for non-invasive screening of positive transformants. The optimal callus induction medium was MS + 2 mg/L 6-BA + 0.3 mg/L NAA + 0.05 mg/L 2, 4-D, with a callus induction rate of 53.33% for leaf explants (the optimal explant for sterile seedlings). The optimal adventitious bud proliferation medium was MS + 2 mg/L 6-BA + 0.1 mg/L NAA, with a proliferation coefficient of 5.87. The optimal rooting medium was 1/2 MS + 0.5 mg/L NAA + 0.5 mg/L IBA, with a 100% rooting rate. The optimal transplant substrate was perlite:vermiculite = 2:1, with a 100% transplant survival rate after acclimatization. For Agrobacterium-mediated transformation, the optimal infection parameters were as follows: Agrobacterium suspension OD600 = 0.6, infection time of 10 min, and 200 μM acetosyringone; the optimal selection conditions were 300 mg/L cefotaxime for bacteriostasis and 30 mg/L hygromycin for transformant screening. The final stable transformation efficiency was 2.50% (95% CI 1.23-3.77%), with an escape rate of 16.13%. Transgenic plants showed distinct purplish-red coloration in roots, stems, and leaves, with significantly higher betacyanin accumulation than wild-type plants (p < 0.05). Stable integration and expression of the RUBY gene were confirmed by PCR, RT-PCR, and RT-qPCR. This study establishes the first efficient regeneration and Agrobacterium-mediated transformation system for Hosta 'Light Star,' and validates the feasibility of the RUBY reporter gene as a visual marker for Hosta transformation. This system provides a solid technical platform for functional genomic studies, CRISPR/Cas9-mediated gene editing, and molecular breeding of ornamental traits in Hosta.

Transformation, Genetic↗

PubMed1992

Circadian rhythm in prostacyclin activity in gastric tissue of the fasting rat.

Gastroduodenal ulcer disease may result from the desynchronization of the circadian rhythms of gastric protective and destructive factors. The purpose of this study was to evaluate whether gastric tissue 6-keto prostaglandin F1 alpha (PGF1 alpha), a catabolic derivative of the putative protective factor prostacyclin, is produced in a circadian fashion in the rat model. Forty-eight male Sprague-Dawley rats were acclimatized in sound-attenuated, lightproof chambers for 3 weeks on a 12:12 hour light/dark entrainment schedule. After an 18-hour fast, six rats were killed at each of eight sampling times. The stomachs were exposed, removed, and assayed for total 6-keto PGF1 alpha content by radioimmunoassay. Cosinor analysis of the data showed significant (p = 0.0262) circadian rhythmicity in 6-keto PGF1 alpha content with an acrophase (peak time) value of 0503 HALO (hours after lights on) or in the middle of the lights-on inactive period for the rats. Hypothetically, the circadian rhythm in some gastric protective factors may render the gastric mucosa vulnerable to injury in a circadian fashion.

6-Ketoprostaglandin F1 alpha↗

PubMed1993

Development of tolerance after repeated administration of a selective muscarinic M1 antagonist biperiden in healthy human volunteers.

The muscarinic antagonist biperiden produces a dose-dependent inhibition of (REM) sleep on acute administration. The present study addressed the possibility of pharmacological tolerance after repeated biperiden administration. Six healthy volunteers were studied under sleep laboratory conditions in the following situations: one acclimatization, night, two baseline (that were averaged), 4 nights of biperiden administration, and 4 nights of placebo recovery administration. Six milligrams of biperiden and placebo were administered in identical capsules. Volunteers and technicians were blind to the order of the administration of the capsules. REM sleep time was reduced during the first and the second night, but was not significantly different in comparison with baseline by the third night. During placebo recovery nights, REM sleep time was not different from baseline. REM sleep latency was increased during the first and second nights of biperiden administration, but tolerance to this effect was observed by the third night. On placebo nights a dramatic shortening of REM latency was observed. The present findings support the hypothesis that anticholinergic drugs, even a selective M1 antagonist such as biperiden, induce tolerance soon after administration. A similar effect has been reported with scopolamine, a nonselective muscarinic antagonist, but the main difference is that biperiden withdrawal was not followed by an REM sleep rebound. The observed effect on REM sleep latency during placebo administration may be related to a supersensitivity to muscarinic M-1 receptors that trigger the first REM sleep period. Because short REM latency has been the main finding in the sleep of depressed patients, some implications of the present findings are discussed.

Adult↗

PubMed1981

Changes in the levels of cyclic nucleotides in rat brain during the sleep-wakefulness cycle.

Changes in the levels of adenosine 3',5'-monophosphate (cAMP) and guanosine 3',5'-monophosphate (cGMP) in the discrete regions of rat brain during the sleep-wakefulness cycle were studied using a microwave fixation method. Rats were restrained in a specially designed frame in which they could move their heads and extremities freely and take food and water ad libitum. The rats were acclimatized to the microwave applicator for 1 h a day for 5-7 days, and then they were sacrificed by microwave irradiation of the heads under polygraphic monitoring. This procedure made it possible to obtain tissue for the analysis of cyclic nucleotides at different times during the sleep-wakefulness cycle. The content of cAMP in the various regions of the brain except the cerebellum decreased during sleep. In the hippocampus, midbrain, pons-medulla and cerebellum, the level of cGMP was highest during wakefulness, whereas in the striatum it was highest during paradoxical sleep. In the midbrain and pons-medulla, the level of cGMP was higher during paradoxical sleep than during slow-wave sleep. These changes of cyclic nucleotide contents may reflect the changes in the release of putative neurotransmitters during the sleep-wakefulness cycle. Our findings suggest that cyclic nucleotides may play some roles in the regulation of the sleep-wakefulness cycle.

Adrenal Glands↗

PubMed1996

Effects of amphetamine at the beginning of the light cycle on multiple indices of motor activity in the rat.

The motor effects of a single dose of d-amphetamine on internally synchronized male Sprague Dawley rats and its dose response relationship at the beginning of the light cycle was investigated using a computerized monitoring system. After 7 days of acclimatization to light/dark cycle and 2 days of baseline monitoring, rats were randomized to a no-treatment time control group (n = 12) or to receive 0 (vehicle), 0.6, 1.25, 2.5, or 10 mg/kg d-amphetamine (n = 8 each) 1 h into the light cycle of day 3, and monitored for an additional post-treatment day 4. In the time control group, there was a stable baseline level of activity for both light and dark phases. All doses (0.6, 1.25, 2.5, and 10 mg/kg) significantly elevated (P < 0.01) locomotor activity compared to baseline, but not all activity parameters (horizontal activity, total distance, vertical activity, stereotypic activity, and number of stereotypic movements) followed the same pattern of response. The maximum increase in all parameters, except vertical activity, occurred at 1.25 mg/kg (P < 0.001). The duration of drug effect increased with dose, with increased activity lasting until the fifth hour after injection of 10 mg/kg. ANOVA revealed no consistent long term effects, with all parameters returning to baseline levels on the day after treatment. The range of variables and the establishment of baseline values at the time of injection for each rat provides the potential to characterize circadian patterns of locomotor activity and chronopharmacologic effects of drugs on motor activity, including sensitization and tolerance.

Amphetamine↗

PubMed1986

Baroreceptor sensitivity during desynchronized sleep.

Sleep is characterized by periods of cortical and subcortical desynchronization similar to that observed during arousal. Because baroreflex control of heart rate is suppressed in the aroused state, the present study compared the cardiac index of baroreflex sensitivity in awake cats with that during desynchronized sleep to determine the level of arousal and its affect on autonomic regulation. Cats were prepared for long-term arterial pressure, cortical, and subcortical EEG and EMG recording. After acclimatization to the laboratory, cats engaged in spontaneous periods of desynchronized sleep. During this period, a bolus of angiotensin II was injected i.v. and the subsequent change in the R-R interval of the cardiac cycle was recorded during the rising phase of the pressor response. These values were compared with values obtained from the same cats during quiet and active wakefulness and those obtained during drug-induced desynchronized sleep with gamma-hydroxybutyrate. The values obtained during naturally occurring desynchronized sleep were comparable to those observed during drug-induced desynchronized sleep. In contrast, the increase in the R-R interval in awake cats, particularly quiet ones, was greater than that seen during desynchronized sleep or during active periods in the awake animal. These data suggest that there is a correlation between the level of arousal, as measured by EEG activity, and the cardiomotor component of baroreflexes.

Animals↗

PubMed1992

Influence of temperature and photoperiod on plasma melatonin in the mudpuppy, Necturus maculosus.

A melatonin (MEL) radioimmunoassay employed previously only in mammals was used to estimate plasma MEL in a salamander, Necturus maculosus. Validation procedures included thin-layer chromatography of plasma extracts, parallel inhibition curves of authentic MEL and serially diluted plasma and plasma extracts and quantitative recovery of authentic MEL added to pooled Necturus plasma. A diel cycle of plasma MEL was demonstrated in mudpuppies acclimatized for a minimum of 3 weeks under a 12L:12D photoperiod and 15 +/- 1 degrees and sampled in late March. The MEL cycle persisted under a reversed photoperiod (lights on, 1800 hr), but the amplitude of the MEL peak was diminished, and the peak was more than 180 degrees out of phase with the corresponding peak under a normal photoperiod. In animals acclimated to 5 degrees in mid-June under a 12L:12D photoperiod, the diel cycle of plasma MEL continued, but both midphotophase and midscotophase concentrations were reduced compared with 15 degrees controls. The diel cycle was also present in animals acclimated to 25 degrees, but the decrease in MEL concentrations was less marked than that in 5 degrees animals. Photoperiod is apparently the primary cue for cycles in plasma MEL in Necturus, but the cycle can be influenced by temperature.

Animals↗

PubMed1985

Comparative pathology of the enlarged carotid body.

A histological study was made of the carotid bodies of man and various animal species from low and high altitudes. The animals studied were the alpaca, llama, cattle, guinea-pig, rabbit, dog, rat and man. As well as a qualitative microscopic study, a differential cell count was carried out to determine the percentage of the light and dark variants of chief cells and of sustentacular cells present. The investigation showed that the carotid bodies enlarge in cattle, guinea-pigs and rabbits living in the hypobaric hypoxia of high altitude to which they have to acclimatize. The carotid bodies are not enlarged in llamas and alpacas which show Darwinian adaptation to high altitude. There is no single histopathological appearance to be found with enlargement of the carotid body; on the contrary, there appears to be a characteristic histological reaction for different species. Thus, man shows hyperplasia of sustentacular cells, cattle show focal dark cell proliferation and rabbits, guinea-pigs, and dogs show striking hyperplasia and vacuolation of chief cells. In the rat, the enlargement of the carotid body is not characterized by the differential proliferation of any specific element and, as a result, it does not appear to be a good model for the human organ. In man and rat, carotid body enlargement occurs in response to systemic hypertension as well as to chronic hypoxaemia and the histological response to the 2 stimuli is the same, depending on the species. The normal rabbit carotid body is more reminiscent of that of man but, in this species, the reaction of glomic tissue differs from that of human glomic tissue.

Altitude↗

PubMed1985

Hibernation "trigger" alters renal function in the primate.

Macaque monkeys acclimatized to a restraint chair were fitted with indwelling venous and urinary catheters. After basal rates of urine production and creatinine clearance were determined, a 50 mg dose of plasma dialysate albumin fraction obtained from the woodchuck was administered intravenously in a total volume of 2.5 ml. Plasma fractions were collected during the winter interval of hibernation (hibernation "trigger" or HT), or during the summer active (SAWA) period. Although the SAWA fraction exerted no effects on renal function, HT caused a significant reduction in creatinine clearance. In addition, a tendency toward reduced urine flow and creatinine production occurred following the HT infusion. These findings suggest that over and above the hypothermia, aphagia and opioid-like behavioral depression induced by HT, the albumin fraction (HT) present endogenously in the woodchuck during winter torpor, exerts a direct action on the kidney of the primate, possibly on the mechanisms underlying glomerular filtration and the tubular reabsorption process.

Animals↗

PubMed1993

Season affects tolerance of cohabitation by deer mice.

We measured the resting metabolic rates of Peromyscus maniculatus for 7 days before and 7 days following forced pairing in order to determine whether seasonal light cycles influenced the rates of behavioral and metabolic habituation of deer mice to cohabitation. We had earlier shown that winter photoperiod and/or huddling results in lower resting metabolic rates and core temperatures of deer mice. Seasonal photoperiods were simulated by conditioning wild-caught mice to 24-h light cycles with differing durations of light exposure during the 24 h day. These experiments demonstrated that winter mice adjusted their resting metabolic rates from solitary to huddling levels much more rapidly than summer mice. Initial, high metabolic rate responses of paired mice persisted much longer than expressions of agonistic behaviors between paired mice. We propose that winter photoperiod enables animals to more efficiently make the transition to spontaneous, amicable huddling as a winter acclimatization strategy.

Animals↗

PubMed1980

Oxygen transport during progressive hypoxia in high-altitude and sea-level waterfowl.

Under conditions of progressive hypoxia, oxygen transport was compared in bar-headed geese (Anser indicus), a species which breeds on the Tibetan Plateau and migrates at altitudes up to 9200 m, and Pekin ducks (Anas platyrhynchos, forma domestica), a similarly sized, sea-level water fowl that does not fly. Pekin ducks showed no altitude-induced behavioral effects (e.g., restlessness) up to 7620 m, while bar-headed geese tolerated 10,668 m with no observable behavioral changes. Ventilatory and cardiac responses to hypoxia as functions of PaO2 followed a typical hyperbolic contour, but the response began at almost 20 Torr lower in the bar-headed goose. Both ventilation and cardiac output appeared to follow a common response curve for the two species, when the independent variable was expressed as arterial oxygen content. The goose had a high oxygen affinity hemoglobin, compared with the duck; the oxyhemoglobin curves of both shifted slightly to the right as a result of acclimation to 5640 m; but only the duck developed erythrocytosis as a consequence of acclimation. Under sea level conditions the duck maintained a higher mixed venous PO2, but with acute hypoxic exposures PVO2 was higher in the goose. Following acclimation, cardiac output in the duck was lower than in pre-acclimatized state, but in the goose it was higher up to the altitude at which it migrates. The selective pressures leading to the evolution of favorable oxygen transport in the bar-headed goose are discussed.

Adaptation, Physiological↗

PubMed1985

Peripheral circulatory responses to 96 hours of eucapnic hypoxia in conscious sheep.

Conscious sheep acclimatizing to hypoxia (PaO2 40 mm Hg, PaCO2 24 mm Hg) respond with increases in cardiac output (Qco) and cerebral blood flow lasting for 24 and 48 h, respectively. Coronary flow increases in a sustained fashion, while there are progressive decreases in renal, splenic and pancreatic flows. In the present study, 5 adult ewes were exposed to similar levels of normobaric hypoxia (PaO2 40 mm Hg) but the PaCO2 was maintained at eucapnic levels (32 mm Hg). VE increased (+210%) while VO2 decreased by 35%. Ventilatory sensitivity to CO2 was unchanged. Qco (thermodilution) was elevated for 96 h (+20%) as stroke volume was maintained at normoxic levels and heart rate increased (+36%). Pulmonary artery pressure increased (+35%) along with plasma catecholamine levels (+116-196%). There were sustained elevations of cerebral flow (radiolabelled microspheres) from 79.1 (+/- 9.2 SEM) to 121.6 ml X min-1 X 100 g-1 (+/- 10.8), coronary flow from 183 (+/- 22.1) to 373 ml X min-1 X 100 g-1 (+/- 46.3), diaphragm flow (+400%) and intercostal muscle flow (+186%) with no apparent redistribution of Qco. Therefore, the cardiac and peripheral circulatory response patterns are altered significantly in eucapnic hypoxia. The rate of O2 delivery to brain and several abdominal viscera is higher.

Animals↗