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

Bombesin-like peptides are widely distributed in the mammalian central nervous system and appear to participate in the regulation of a variety of autonomic functions. Bombesin has been shown to alter feeding behavior, locomotor activity, and thermoregulation. Microinfusion of bombesin into the preoptic area of the hypothalamus produces a reduction in core body temperature, but only if the rat has been cold-exposed, food-deprived, or pretreated with insulin. The mechanism for bombesin-induced hypothermia under the latter two conditions is unknown. The present study evaluated the possible contribution of peripheral heat loss mechanisms in bombesin-induced hypothermia. Rats were administered insulin (10U/kg, Regular Iletin I i.m.) or saline followed by an intrahypothalamic injection of bombesin (.05 microgram/.25 microliter) or peptide vehicle. Rectal and tail-skin temperatures were measured continuously for 120 min. Changes in temperature were evaluated at 30, 60, 90, and 120 min., using analysis of variance. As previously demonstrated, bombesin produced hypothermia in rats pretreated with insulin. This reduction in core temperature was not associated with any significant alteration in tail-skin temperature. Results suggest that bombesin-induced hypothermia in rats pretreated with insulin may not be mediated by an increase in peripheral heat loss.
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PMID:Bombesin-induced hypothermia in the insulin-treated rat: effect on tail-skin temperature. 269 93

The thermal responses of rats which were pretreated with 5,7-dihydroxytryptamine to deplete hypothalamic 5-hydroxytryptamine, 6-hydroxydopamine to deplete hypothalamic catecholamines, phentolamine and propranolol to inhibit adrenergic receptors, haloperidol to inhibit dopamine receptors, or atropine to inhibit cholinergic receptors, to intrahypothalamic administration of bombesin were compared with those of control rats. The bombesin-induced hypothermia was attenuated by pretreatment of the rats with either hypothalamic dopamine depletion or receptor blockade, or hypothalamic cholinergic receptor blockade. The reduction in the bombesin-induced hypothermia in the treated rats was due to the reduction of metabolic and vasomotor response. The data indicate that bombesin may act on hypothalamic dopamine and/or cholinergic receptor mechanisms to induce hypothermia by promoting a reduction in metabolic heat production and an enhancement in heat loss in rats.
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PMID:Bombesin-induced hypothermia: possible involvement of cholinergic and dopaminergic receptors in the rat hypothalamus. 287 38

The effect of dermorphin on regulation of body temperature was studied in the rat under extreme and thermoneutral environmental temperatures and in different nutritional states. Intracerebroventricular (icv) injections of dermorphin at dose levels of 10, 50, 100 ng/rat produced hypothermia in animals placed in cold temperatures (-10 degrees C and +4 degrees C) and hyperthermia at ambient (+22 degrees C) and higher temperatures (+34 degrees C). These data emphasize the importance of using a wide range of environmental temperatures in studying drug effects on thermoregulation. To determine whether the effect of dermorphin on body temperature was related to the nutritional state of the animal, as observed with other neuropeptides (i.e., bombesin, litorin), the thermoregulatory response was followed in fed and fasted rats. The same results were obtained in both experimental groups. In all cases, dermorphin change in body temperature was mediated via an action on typical opioid receptors since it was completely prevented by pretreatment with naloxone.
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PMID:Effect of dermorphin on body temperature in rats. 289 74

Oxytocin (OXY) administered intracisternally to adult male mice produced a significant dose-related (1-4 micrograms) increase in colonic temperatures at an ambient temperature of 25 degrees C. The maximal rise in temperature occurred 30 min after administration of the peptide. The interactive effects on colonic temperature of central OXY with equimolar amounts of neurotensin, bombesin or beta-endorphin or of 2 2 mg/kg of chlorpromazine were investigated. OXY significantly antagonized the hypothermia produced by all of these substances. Pretreatment of mice with haloperidol or naloxone failed to prevent OXY-induced hyperthermia. The hyperthermic action of OXY and the interactive effects of OXY with other peptides on thermoregulation may be physiologically significant during parturition and lactation.
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PMID:Interactive effects of intracisternal oxytocin and other centrally active substances on colonic temperatures of mice. 294 25

A single injection of the hypothermia-inducing neuropeptide bombesin resulted in an excellent recovery system for reisolating viruses from Swiss albino mice infected with vesicular stomatitis virus even up to 90 days after infection. The virus was recovered from a cell homogenate prepared from whole brain tissue 24 h after intracerebral injection of bombesin; brain cells were cocultivated with BHK-21 cell monolayers and then plaqued on BHK-21 cells at 31 degrees C. All of the recovered viruses were identified as vesicular stomatitis virus by antibody neutralization and peptide analyses of some of the structural proteins. However, some of the recovered viruses were altered with regard to tryptic peptide maps, temperature sensitivity, and central nervous system disease induced compared with the viruses used to initiate the infection. Most of the recovered viruses induced a similar disease when reinoculated intracerebrally into mice, characterized by hind-leg paralysis 4 to 6 days after infection. Two of the recovered viruses were lethal, however, resulting in a relatively rapid generalized wasting disease and death in 3 to 4 days.
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PMID:Hypothermia-inducing peptide promotes recovery of vesicular stomatitis virus from persistent animal infections. 298 89

The effects of intraventricular bombesin (BS) at doses of 0.1, 1.0, and 10.0 micrograms on thermoregulatory and cardiovascular functions were studied in conscious rats with a direct calorimeter at ambient temperatures (Ta) of 18, 23, and 28 degrees C. At two lower TaS, the central BS produced a profound decrease in colonic temperature (Tcol) with a reduction of the temperature difference between the interscapular brown adipose tissue (BAT) and the colon (TBAT-Tcol). Increases in nonevaporative and evaporative heat losses and mean arterial blood pressure (BP) were consistent following the central BS at any dose tested at any Ta. In the sinoaortic deafferentated rats, a 0.1 microgram of BS produced hypothermia with a significant decrease in (TBAT-Tcol) and heat production (M). Changes in Tcol, (TBAT-Tcol), and M in the denervated rats, however, were not different from those in the sham-operated rats. These results suggest that the central BS suppresses BAT thermogenesis and facilitates heat loss mechanisms. The baroreflex-mediated metabolic reduction is not the case in the BS-induced hypothermia in rats.
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PMID:Suppression of brown adipose tissue metabolism following intraventricular bombesin in rats. 343 Aug 67

Bombesin, some of its fragments and analogues, being injected intracerebroventricularly, induce rapid decline in body temperature. The active fragment of bombesin--C-terminal nonapeptide--induced a 25% depression of oxygen consumption in cold-exposed rabbits, no changes in the shivering thermogenesis, and a 3.5--5.0-fold increase of ear blood vessels section area accompanied by a gain in linear velocity of blood flow. The peripheral blood flow seems to be the main effector of the bombesin-induced hypothermia.
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PMID:[Bombesin reduces body temperature chiefly by increasing peripheral blood flow]. 356 72

Direct administration of bombesin (1, 10, and 100 ng/microliter) into the preoptic anterior hypothalamic area caused a dose-related fall in rectal temperature at ambient temperatures (Ta) of 8 and 22 degrees C. The hypothermia in response to bombesin was brought about by a decrease in metabolism at Ta 8 degrees C, whereas at Ta 22 degrees C the hypothermia was brought about by both a decrease in metabolism and an increase in cutaneous temperature. However, at Ta 30 degrees C, intrahypothalamic administration of bombesin caused an insignificant change in thermoregulatory responses. On the other hand, 51 single neurons in the preoptic anterior hypothalamic area were examined in 20 rats under urethan anesthesia. Each animal was subjected to scrotal warming or cooling and to the administration of bombesin. Microiontophoretic application of bombesin resulted in inhibition of the majority (62.5%) of cold-responsive neurons as well as excitation of the majority (50%) of warm-responsive neurons recorded in the preoptic anterior hypothalamic area. However, the majority (74%) of thermally unresponsive neurons were not affected by bombesin application. The data indicate that bombesin, when administered intrahypothalamically, excites warm-responsive neurons and inhibits cold-responsive neurons within the preoptic anterior hypothalamic area to induce hypothermia by promoting an increase in heat loss and a decrease in heat production.
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PMID:Effects of bombesin on thermoregulatory responses and hypothalamic neuronal activities in the rat. 374 Mar 12

Norepinephrine, serotonin, and bombesin administered intrahypothalamically affected thermoregulation in the deermouse, Peromyscus maniculatus. At a Ta of 22 degrees C, doses of 3 micrograms and 6 micrograms of NE resulted in transient hypothermia (maximum drop of 1.6 +/- 1.0 degrees C and 4.3 +/- 2.3 degrees C, respectively). A 1.5 microgram dose of 5-HT induced a persistent hyperthermia (maximum increase of 1.8 +/- 0.8 degrees C) which persisted for more than 2 h. A 6 microgram dose of 5-HT did not produce any significant effects. At a Ta of 22 degrees C, doses of 1 ng and 10 ng of bombesin produced a transient hyperthermia (maximum increase of 1.8 +/- 0.3 degree C and 2.1 +/- 1.2 degrees C, respectively) immediately postinjection. At a Ta of 5 degrees C, a 1 ng dose of bombesin resulted in a prolonged hypothermia (maximum decrease of 2.0 +/- 0.4 degrees C), while a 10 ng dose of bombesin produced a hyperthermic response (maximum increase of 1.3 +/- 0.8 degree C) at 2 h postinjection.
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PMID:Effects of intrahypothalamically administered norepinephrine, serotonin and bombesin on thermoregulation in the deermouse (Peromyscus maniculatus). 394 67

In this study we have examined the interactions of bombesin (1 microgram ICV), neurotensin (1 microgram ICV), TRH (10 micrograms ICV), somatostatin (10 micrograms ICV), PGE2 (10 micrograms ICV) and naloxone (10 mg/kg SC) on thermoregulation in the rat at room temperature (20 +/- 1 degree C). Given alone, bombesin, neurotensin, somatostatin and naloxone all produced hypothermia (bombesin greater than neurotensin greater than somatostatin congruent to naloxone). PGE2 was hyperthermic, and TRH had no effect. Bombesin and PGE2 neutralized one another's effects. Neurotensin had no effect on PGE2-induced hyperthermia. Naloxone enhanced the hypothermic effect of bombesin and somatostatin enhanced the rate of onset of hypothermia after bombesin. TRH had no effect on bombesin-induced hypothermia. TRH, somatostatin and naloxone had no effect on neurotensin-induced hypothermia. TRH antagonized the hypothermia due to naloxone and somatostatin.
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PMID:Neuropeptides and thermoregulation: the interactions of bombesin, neurotensin, TRH, somatostatin, naloxone and prostaglandins. 612 11


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