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)

The effects of increasing doses of apomorphine were studied in mice in six nociceptive tests: (1) withdrawal of the tail immersed in hot water, (2) vocalization induced by the electrical stimulation of the tail, (3) tail flick using a radiant beam, (4) withdrawal of a tail-clip, (5) writhing induced by the i.p. injection of phenylbenzoquinone, (6) forepaw licking and jump latencies on a hot plate. Only in the tests (5) and (6), an apparent analgesia was obtained. Differences were observed between tests (5) and (6), as to: (i) the apparent relative effectiveness of (-)sulpiride (more effective in test [5] than in test [6]), (ii) the naloxone-induced modifications of apomorphine effects (whereas naloxone antagonized apomorphine effects in test [6], it did not in test [5]), (iii) the decrease of apomorphine-induced responses by prevention of hypothermia (in test [6] but not in test [5]). These data suggest that APO-induced increased jump latencies are at least partly related with hypothermia and endogenous opioid systems, whereas APO effect on the writhing test depends on the stimulation of dopamine receptors particularly sensitive to sulpiride and is independent from body temperature and opioidergic transmissions.
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PMID:Dissociated effects of apomorphine on various nociceptive responses in mice. 378 51

Apomorphine (APO, 0.25 to 16 mg/kg) induced a dose dependent hypothermia in mice. Haloperidol, a dopamine antagonist, antagonized APO hypothermia due to lower doses. Clozapine and phenoxybenzamine, on the other hand, failed to modify APO hypothermia. Similarly, levopropranolol and cyproheptadine, which modify serotonergic responses, also failed to modify APO hypothermia. But fluxetine which selectively inhibits serotonin uptake, reversed APO induced hypothermia due to higher doses but not that induced by low dose of APO. The behavioral stereotypy was, however, not modified by fluoxetine pretreatment. It is concluded that APO hypothermia due to lower and higher doses are mediated by different receptors and the latter action involves the interaction of more than one type of receptor.
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PMID:Apomorphine hypothermia: interaction with serotonergic agents. 719 60

It is well known that the dopamine (DA) system plays an essential role in the organization and regulation of brain activational processes. Various environmental stimuli that induce locomotor activation also increase DA transmission, while DA antagonists decrease spontaneous locomotion. Our previous work supports close relationships between locomotor activation and brain and body temperature increases induced by salient environmental challenges or occurring during motivated behavior. While this correlation was also true for psychomotor stimulant drugs such as methamphetamine and MDMA, more complex relationships or even inverted correlations were found for other drugs that are known to increase DA transmission (i.e. heroin and cocaine). In the present study we examined brain, muscle and skin temperatures together with conventional locomotion during selective interruption of DA transmission induced by a mixture of D1 and D2 antagonists (SCH-23390 and eticlopride at 0.2 mg/kg, s.c.) and its selective activation by apomorphine (APO; 0.05 and 0.25 mg/kg, i.v.) in rats. While full DA receptor blockade decreased spontaneous locomotion, it significantly increased brain, muscle and skin temperatures, suggesting metabolic brain activation under conditions of vasodilatation (or weakening of normal vascular tone). In contrast, APO strongly decreased skin temperature but tended to decrease brain and muscle temperatures despite strong hyperlocomotion and stereotypy. The brain temperature response to APO was strongly dependent on basal brain temperature, with hypothermia at high basal temperatures and weak hyperthermia at low temperatures. While supporting the role of DA in locomotor activation, these data suggest more complex relationships between drug-induced alterations in DA transmission, behavioral activation and metabolic brain activation.
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PMID:Relationships between locomotor activation and alterations in brain temperature during selective blockade and stimulation of dopamine transmission. 1719 51