Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0020672 (hypothermia)
 17,327 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Offspring of female rats injected daily with methadone (5 mg/kg) or saline were cross-fostered at birth to form groups exposed to methadone during gestation (G), lactation (L), or gestation and lactation (G-L); controls (C) were exposed only to saline. Rectal temperature, body weight and food consumption were measured from postnatal Days 36-51. Ambient temperature was maintained at 21 degrees C except for Days 42--45, when the temperature was 10 degrees C. Group G rats never differed from controls, but offspring in Groups L and G-L were hypothermic at room temperature; Group G-L rats exhibited a further temperature loss during the cold stress. There were no group differences in food consumption after Day 39, and all groups increased food intake while in the cold. Group differences in body weight were not reliable but Group G-L rats gained less weight than the rest during the experiment, whereas Group L rats gained more. These results indicate that, depending upon treatment schedule, perinatal methadone exposure is associated with hypothermia during the postweaning period. A prolonged withdrawal reaction from methadone may account for the impaired thermal regulation.
 ...
PMID:Imparied thermal regulation in juvenile rats following perinatal methadone exposure. 46 83

Hypothermia produced by IV administration of chlorpromazine (CPZ, 0.5-2.0 mg/kg) in a thermoneutral environment was greater in rabbits 2-4.5 years old than in animals under 24 months of age. One microgram CPZ given intracerebroventricularly (ICV) produced greater hypothermia in the older animals in tests performed in a thermoneutral environment while 0.25 and 0.5 microgram doses did not. The hypothermogenic effect of all three ICV doses of CPZ was enhanced in older rabbits exposed to cold. The brain of the older rabbit appears to be more sensitive to the hypothermogenic effects of CPZ. The findings suggest that this widely used tranquilizer can contribute to accidental hypothermia of the aged.
 ...
PMID:Hypothermia produced by peripheral and central injections of chlorpromazine in aged rabbits. 48 19

A symposium was held at the RAF Institute of Aviation Medicine, Farnborough, Hampshire, on Feb. 28, 1978. The purpose of the meeting was to distill up-to-date expert opinion to provide advice for those faced with the treatment of victims of exposure or cold water immersion. In particular, it was intended to recommend practical measures which could be employed in the field. However, it soon became apparent that there are large gaps in our knowledge of the physiology of hypothermia. These made the formulation of definitive advice extremely difficult.
 ...
PMID:The treatment of acute accidental hypothermia: proceedings of a symposium held at the RAF Institute of Aviation Medicine. 49 54

The effects of alcohol on core cooling rates (rectal and tympanic), skin temperatures, and metabolic rate were determined for 10 subjects rendered hypothermic by immersion for 45 min in 10 degrees C water. Experiments were duplicated with and without a 20-min period of exercise at the beginning of cold water immersion. Measurements were continued during rewarming in a hot bath. With blood alcohol concentrations averaging 82 mg 100 mL-1, core cooling rates and changes in skin temperatures were insignificantly different from controls, even if the exercise period was imposed. Alcohol reduced shivering metabolic rate by an overall mean of 13%, insufficient to affect cooling rate. Alcohol had no effect on metabolic rate during exercise. During rewarming by hot bath, the amount of 'afterdrop' and rate of increase in core temperature were unaffected by alcohol. It was concluded that alcohol in a moderate dosage does not influence the rate of progress into hypothermia or subsequent, efficient rewarming. This emphasizes that the high incidence of alcohol involvement in water-related fatalities is due to alcohol potentiation of accidents rather than any direct effects on cold water survival, although very high doses of alcohol leading to unconsciousness would increase rate of progress into hypothermia.
 ...
PMID:Effect of alcohol on thermal balance of man in cold water. 49 99

To determine whether cold could activate the kallikrein-kinin system in vivo as it does in vitro, the circulating systemic concentrations of bradykinin were serially measured in 10 cyildren with congenital diseases of the heart undergoing corrective cardiac surgery. Bradykinin was measured by radioimmunoassay in blood samples obtained before, during and after profound hypothermia (to 18 degrees C) and cardiopulmonary bypass. The circulating concentrations of bradykinin increased significantly as body temperature decreased during surface cooling. The increase in circulating bradykinin was associated with a decrease in the circulating level of bradykininogen, the precursor of bradykinin. With the onset of cardiopulmonary bypass and hence, removal of the lung and pulmonary converting enzyme from the circulation, there was a further rise in the already elevated concentrations of bradykinin. This is the first in vivo demonstration that hypothermia leads to an increase in the circulating concentrations of bradykinin.
 ...
PMID:Increased circulating bradykinin during hypothermia and cardiopulmonary bypass in children. 49 78

Potassium (34 mEq/L) cardioplegia was induced with cold blood (CBK) in three groups of six dogs undergoing 60 minutes of myocardial ischemia at a systemic temperature of 27 degrees +/- 2 degrees and a myocardial temperature of 7 degrees +/- 2 degrees C (crushed ice). Group 1 (CBK) animals were reperfused initially with 400 ml cold blood over 8 to 10 minutes at increasing pressures of up to 75 mm Hg. Group II (CBK-K) dogs were reperfused in the same manner as Group I with the addition of potassium chloride, 30 mEq/L. In Group III (CBKG-KG) glutathione, 30 mg/100 ml, was added to both the pre- and postischemic perfusions with CBK. After 30 minutes of reperfusion control studies were repeated. Heart rate, peak systolic pressure, rate of rise of left ventricular pressure, maximum velocity of contractile element, pressure-volume curves, coronary flow distribution, muscle stiffness, and heart water were not significantly different from control values. Total coronary flow and myocardial uptake of oxygen, lactate, and pyruvate did not serve to separate the three groups; the same was true for right ventricular creatine phosphate, adenosine triphosphate, and adenosine diphosphate during ischemia and recovery. Ultrastructural myofibrillar lesions were noted in all groups. thus, postischemic cardioplegia and use of a physiological reducing agent do not enhance CBK cardioplegia with topical and systemic hypothermia.
 ...
PMID:Cold-blood potassium cardioplegia: evaluation of glutathione and postischemic cardioplegia. 50 72

Rats with dietary potassium (K) depletion have an altered breathing pattern compared to age matched control rats. The K depleted rats also have a decreased body weight gain, basal metabolic rate and body temperature. In this study, age matched controls are underfed (UFC) to match for body weight gain and metabolic rate and controls are exposed to different ambient temperatures to alter metabolism and body temperature. Compared to UFC rats with the same body weight and basal metabolic rate the K depleted rats breathe slower and with a larger tidal volume in the basal state and in response to hypercapnia and hypoxia. With heat stress body temperature is increased in K depleted rats as is metabolic rate. While frequency is increased it is still slower than in controls at the same ambient and body temperatures. We conclude that the low metabolic rate and body temperature of K depleted rats is not the cause of the altered breathing pattern. In addition, it is shown that the hypothermia of K depletion is present only at ambient temperatures below the thermoneutral zone and that is is apparently due to an inability of the K depleted rat to increase metabolic heat production with cold stress.
 ...
PMID:Breathing in the potassium depleted rat: the role of metabolic rate and body temperature. 50 31

Intraperitoneal administration of either haloperidol or chlorpromazine produced hypothermia both in the cold (8 degrees C) and at room temperature (22 degrees C). The hypothermia was brought about both by a decrease in metabolic heat production and an increase in the cutaneous temperature of tail and foot skin. However, at a higher temperature (29 degrees C), there were no changes in rectal temperature and other thermoregulatory responses.
 ...
PMID:Haloperidol produces hypothermic effects in rats. 51 Apr 85

The heart and diaphragm efficiency seems to be an actively regulated variable. It alters in prolonged adaptation (raises in adaptation to hypoxia; diminishes in cold adaptation which means an increase in heat production per unit of muscle's contractile activity). Enhancement of noradrenaline calorigenic effect on skeletal muscles during cold adaptation is corroborated in an isolated diaphragm. Diminishing of the heart and diaphragm efficiency in thyrotoxicosis suggests participation of thyroid hormones in formation of adaptive decrease of muscular contraction efficiency in cold adaptation. The heart efficiency raises in hypothermia and, probably, in limitation of the myocardium oxygen supply. Possible mechanisms of changes of muscular contraction efficiency are discussed.
 ...
PMID:[Changes in the efficiency coefficient of the heart and diaphragm during cold adaptation]. 51 Jun 17

To study the effects of preinduced hypothermia on the physiological and thermoregulatory responses to exercise in the heat rats were intravenously administered either 100 micrograms of chlorpromazine (CPZ) or 200 mg/kg of L-tryptophan (L-Trp) under restraint in a cold (4 degrees C) environment. When rectal temperatures (Tre) reached 32-33 degrees C the rats were removed to a hot environment (35 degrees C) where they ran on a level treadmill (9.14 m/min) to hyperthermic exhaustion (Tre, 42.5-43 degrees C). Both CPZ and L-trp hypothermia was effective in increasing significantly (P less than 0.001) the time to hyperthermic exhaustion. However, the maximal Tre and skin temperatures (Tsk) attained were unaffected by either treatment. When the rats exercised on the treadmill, increments (degrees C/min) in Tre and Tsk were significantly (P less than 0.02, minimal) greater for the initially hypothermic animals compared to normothermic controls. Cooling rates were unaffected by either treatment. We concluded from these studies that, although preinduced hypothermia is extremely effective in prolonging the time to hyperthermic exhaustion, no additional beneficial thermoregulatory responses accrued as a result of this treatment.
 ...
PMID:Hypothermia induced by chlorpromazine or L-tryptophan: effects on treadmill performance in the heat. 51 90


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>