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)

Metabolic depression, an adaptive biological process for energy preservation, is responsible for torpor, hibernation and estivation. We propose that a form of metabolic depression, and not mitochondrial dysfunction, is the process underlying the observed hypometabolism, state-dependent neurobiological changes and vegetative symptoms of major depression in humans. The process of metabolic depression is reactivated via differential gene expression in response to perceived adverse stimuli in predisposed persons. Behavior inhibition by temperament, anxiety disorders, genetic vulnerabilities, and early traumatic experiences predispose persons to depression. The proposed theory is supported by similarities in the presentation and neurobiology of hibernation in bears and major depression and explains the yet unexplained neurobiological changes of depression. Although, gene expression is suppressed in other hibernators by deep hypothermia, bears were chosen because they hibernate with mild hypothermia. Pre-hibernation in bears and major depression with atypical features are both characterized by fat storage through overeating, oversleeping, and decreased mobility. Hibernation in bears and major depression with melancholic features are characterized by withdrawal from the environment, lack of energy, loss of weight from not eating and burning stored fat, changes in sleep pattern, and the following similar neurobiological findings: reversible subclinical hypothyroidism; increased concentration of serum cortisol; acute phase protein response; low respiratory quotient; oxidative stress response; decreased neurotransmitter levels; and changes in cyclic-adenosine monophosphate-binding activity. Signaling systems associated with protein phosphorylation, transcription factors, and gene expression are responsible for the metabolic depression process during pre-hibernation and hibernation. Antidepressants and mood stabilizers interfere with the hibernation process and produce their therapeutic effects by normalizing the fluctuation of activities in the different signaling systems, which are down-regulated during hibernation and depression and up-regulated during exodus from hibernation and the hypomanic or manic phase of mood disorders. The ways individuals cognitively perceive, understand, communicate, and react to the vegetative symptoms of depression, from downregulation in energy production, and in the absence of known medical causes, produce the other characteristics of depression including guilt, helplessness, hopelessness, suicidal phenomena, agitation, panic attacks, psychotic symptoms, and sudden switch to hypomanic or manic episodes. The presence of one or more of these characteristics depends on the person's neuropsychological function, its social status between the others, and the other's response to the person. Neurobiological changes associated with metabolic depression during entrance, maintenance, and exodus from hibernation in bears is suggested as a natural animal model of human depression and mood disorders.
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PMID:Metabolic depression in hibernation and major depression: an explanatory theory and an animal model of depression. 1606 29

The case of a 63-year-old woman who presented with status epilepticus, coma and hypoventilation is reported. A primary neurological cause was considered. Hypothermia led to further investigations and a diagnosis of severe hypothyroidism. The neurological complications of hyperthyriodism include alteration in mental status with slowness, decreased concentration and lethargy, headache, cranial nerve palsies, dysarthria, hoarseness, myopathy, neuropathy, reflex changes, ataxia, and psychotic episodes. Our patient suffered from a rare consequence of severe hypothyroidism presenting with status epilepticus and she died despite treatment. To our knowledge this is the second patient to be reported with myxoedema coma with this kind of presentation. Despite therapeutic options, there is a high mortality rate.
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PMID:Status epilepticus caused by a myxoedema coma. 1712 58

In female rats olanzapine (4 mg/kg b.i.d., i.p.) induced acute hypothermia, followed by very rapid full tolerance. With more prolonged treatment (over > 10 days) the hypothermic effect of olanzapine was reinstated. Subsequent withdrawal after 18 days of treatment induced very rapid onset (within 1 day) hyperthermia, which was time limited, dissipating completely over 3-4 days. These findings are similar to previous findings with clozapine [Goudie A Smith J Robertson A Cavanagh C (1999). Clozapine as a drug of dependence. Psychopharmacology; 142: 369-374.]. Although the mechanism(s) involved in the secondary hypothermic effect of olanzapine are, at present, unclear; the withdrawal hyperthermia observed represents the first report of a clear discontinuation effect of olanzapine. Such discontinuation effects are probably observed with many antipsychotic drugs. Since they have been suggested to facilitate relapse to psychosis and to interfere with subsequent clinical responses to antipsychotics, they merit further detailed analysis in both clinical and preclinical studies.
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PMID:Olanzapine withdrawal/discontinuation-induced hyperthermia in rats. 1768 64

Compounds with anti-glutamatergic properties currently in clinical use for various indications (eg Alzheimer's disease, epilepsy, psychosis, mood disorders) have potential utility as novel treatments for alcoholism. Enhanced sensitivity to certain acute intoxicating effects (ataxia, sedative) of alcohol may be one mechanism by which anti-glutamatergic drugs modulate alcohol use. We examined the effects of six compounds (memantine, dextromethorphan, haloperidol, lamotrigine, oxcarbazepine, and topiramate) on sensitivity to acute intoxicating effects of ethanol (ataxia, hypothermia, sedation/hypnosis) in C57BL/6J mice. Analysis of topiramate was extended to determine the influence of genetic background (by comparison of the 129S1, BALB/cJ, C57BL/6J, DBA/2J inbred strains) and prior stress history (by chronic exposure of C57BL/6J to swim stress) on topiramate's effects on ethanol-induced sedation/hypnosis. Results showed that one N-methyl-D-aspartate receptor (NMDAR) antagonist, memantine, but not another, dextromethorphan, potentiated the ataxic but not hypothermic or sedative/hypnotic effects of ethanol. Haloperidol increased ethanol-induced ataxia and sedation/hypnosis to a similar extent as the prototypical NMDAR antagonist MK-801. Of the anticonvulsants tested, lamotrigine accentuated ethanol-induced sedation/hypnosis, whereas oxcarbazepine was without effect. Topiramate was without effect per se under baseline conditions in C57BL/6J, but had a synergistic effect with MK-801 on ethanol-induced sedation/hypnosis. Comparing inbred strains, topiramate was found to significantly potentiate ethanol's sedative/hypnotic effects in BALB/cJ, but not 129S1, C57BL/6J, or DBA/2J strains. Topiramate also increased ethanol-induced sedation/hypnosis in C57BL/6J after exposure to chronic stress exposure. Current data demonstrate that with the exception of MK-801 and haloperidol, the compounds tested had either no significant or assay-selective effects on sensitivity to acute ethanol under baseline conditions in C57BL/6J. However, significant effects of topiramate were revealed as a function of co-treatment with an NMDAR blocker, genetic background, or prior stress history. These findings raise the possibility that topiramate and possibly other anti-glutamatergic drugs could promote the acute intoxicating effects of ethanol in specific subpopulations defined by genetics or life history.
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PMID:Effects of topiramate and other anti-glutamatergic drugs on the acute intoxicating actions of ethanol in mice: modulation by genetic strain and stress. 1884 65

Hypothermia and rhabdomyolysis are infrequent adverse effects of antipsychotic drugs. Here we report a case of an adolescent with schizophreniform disorder who developed both of them simultaneously after intramuscular injection of olanzapine. A 17-year-old male patient was hospitalized for treatment of psychotic symptoms, which persisted on risperidone 3 mg/day for 3 weeks. Then his antipsychotic drug was shifted to oral olanzapine 10 mg/day. The next day, he received intramuscular injection of olanzapine 5 mg and soon developed hypothermia, rhabdomyolysis, hypotension and bradycardia. These symptoms subsided gradually in the next 2 weeks after supportive treatment was given. Such adverse effects were not observed in the following 7 months. Possible pharmacological mechanisms were discussed. Physicians should be cautious about patients' clinical symptoms after giving olanzapine injection or rapid titration in dosage.
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PMID:Hypothermia and rhabdomyolysis following olanzapine injection in an adolescent with schizophreniform disorder. 1955 99

Neurotensin, a tridecapeptide, is widely distributed in the brain and gastrointestinal tract. It possesses analgesic, hypothermic, and antipsychotic-like properties. Neurotensin's effects are mediated mainly through two receptor subtypes, NTS1 and NTS2. Activation of NTS1 has been implicated in most of the pharmacological effects of neurotensin but is associated with hypothermia and hypotension. We report on a novel neurotensin analog with higher selectivity to NTS2, namely, NT79, which exhibits selective behavioral effects. NT79 was tested in animal models for pain (thermal-hot plate test; visceral-acetic acid-induced writhing test), and in animal models that are predictive of antipsychotic-like effects (apomorphine-induced climbing; d-amphetamine-induced hyperactivity; disruption of prepulse inhibition). Its effects on body temperature and on blood pressure were also determined. Neurochemical changes in extracellular neurotransmitters were measured using in vivo microdialysis while the rats were simultaneously evaluated for acetic acid-induced writhing with and without pretreatment with NT79. Binding data at molecularly cloned hNTS1 and hNTS2 suggest selectivity for hNTS2. NT79 blocked the acetic acid-induced writhing with an ED(50) of 0.14 microg/kg while having no effect on thermal nociception. The writhing was paralleled by an increase in 5-HT which was attenuated by NT79. NT79 demonstrated antipsychotic-like effects by blocking apomorphine-induced climbing, d-amphetamine-induced hyperactivity, and reducing d-amphetamine- and DOI-induced disruption of prepulse inhibition. Uniquely, it caused no significant hypothermia and was without effect on blood pressure. NT79, with its higher selectivity to NTS2, may be potentially useful to treat visceral pain, and psychosis without concomitant side effects of hypothermia or hypotension.
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PMID:NT79: A novel neurotensin analog with selective behavioral effects. 1987 4

The antipsychotic drug zotepine [ZTP; 2-[(8-chlorodibenzo[b,f]thiepin-10-yl)oxy]-N,N-dimethylethan-1-amine] is known to have not only atypical antipsychotic effects but also antidepressive effects in schizophrenia patients. Norzotepine [norZTP; N-desmethylzotepine, 2-[(8-chlorodibenzo[b,f]thiepin-10-yl)oxy]-N-methylethan-1-amine] has been postulated to be a major metabolite of ZTP in humans. Here, we characterized norZTP through several in vitro studies and in animal models of psychosis, depression, and extrapyramidal symptoms (EPS) and compared the pharmacological profiles with those of ZTP. Although both compounds showed similar overall neurotransmitter receptor binding profiles, norZTP showed 7- to 16-fold more potent norepinephrine reuptake inhibition than ZTP. In a pharmacokinetic study, both ZTP and norZTP showed good brain permeability when administered individually in mice, although norZTP was not detected in either plasma or brain after intraperitoneal injection of ZTP. In the methamphetamine-induced hyperlocomotion test in mice, norZTP and ZTP showed similar antipsychotic-like effects at doses above 1 mg/kg i.p. In contrast, unlike ZTP, norZTP did not induce catalepsy up to 10 mg/kg i.p. norZTP significantly antagonized the hypothermia induced by reserpine [(3beta,16beta,17alpha,18beta,20alpha)-11,17-dimethoxy-18-[(3,4,5-trimethoxybenzoyl)oxy]yohimban-16-carboxylic acid methyl ester], suggesting in vivo inhibition of the norepinephrine transporter. In the forced-swim test, norZTP exerted an antidepressant-like effect at the effective doses for its antipsychotic action, whereas ZTP neither antagonized reserpine-induced hypothermia nor showed antidepressant-like effect. These results collectively demonstrate that norZTP exerts more potent inhibitory action than ZTP on norepinephrine transporters both in vitro and in vivo, presumably accounting for its antidepressant-like effect and low EPS propensity. Given that norZTP is the major metabolite observed in humans, norZTP may contribute to the unique clinical profiles of its mother compound, ZTP.
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PMID:Norzotepine, a major metabolite of zotepine, exerts atypical antipsychotic-like and antidepressant-like actions through its potent inhibition of norepinephrine reuptake. 2022 78

A 20-year-old woman with borderline personality disorder was referred to the emergency department by a psychiatric clinic. After taking 10 g of nutmeg she complained of stomach ache and dizziness. A physical examination showed mild hypothermia and sinus tachycardia. She was admitted for observation and discharged after 24 h to the psychiatric clinic without sequelae. Nutmeg is a spice. Relatively unknown are the hallucinogenic and euphoric effects for which it is used by drug abusers and students. Symptoms appear 6 h after ingestion of at least 10 g of nutmeg and are related to its effects on the central nervous system. Use of the drug can lead to anxiety and feelings of doom and even to psychosis. Dry mouth, nausea and dizziness may also occur. A physical examination may show hypothermia, tachycardia or hypertension or, in rarer cases, hypotension and shock. Symptoms disappear without sequelae after 24-48 h. Treatment consists of supportive measures. In the event of haemodynamic instability, cardiovascular monitoring is indicated.
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PMID:[Unusual use of nutmeg]. 2085 16

The use of treatment with antipsychotic drugs highlights the difficulty of finding the right balance between the benefit on psychotic symptoms and the risk of the occurrence of adverse reactions. There is a strong genetic and pharmacological evidence supporting the hypothesis that activation of D2 receptors could lead to hypothermia and that the treatment haloperidol is capable of inducing hypothermia apomorfino similarily in laboratory animals. It also seems that, haloperidol is not the only antipsychotic able to determine this type of reaction, as some evidence suggests that other drugs such as reserpine, chlorpromazine would be capable of inducing hypothermia. Finally, while some studies suggest the possible occurrence of haloperidol-induced hypothermia only in laboratory animals, other authors argue that this same reaction can occur in humans as well. In this report, we describe the cases, rarely witnessed in the literature, of three patients in whom the administration of haloperidol caused hypothermia.
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PMID:What about temperature? Haloperidol-induced hypotermia. 2405 Nov 46

Oseltamivir is contraindicated for people aged 10-19 in principle in Japan, due to concern about abnormal behaviours. Sudden death is another concern. This review examines growing evidence of their association and discusses underlying mechanisms of these sudden-onset type reactions to oseltamivir. First, the importance of animal models and the concept of human equivalent dose (HED) is summarized. Second, the specific condition for oseltamivir use, influenza infection, is reviewed. Third, findings from toxicity studies conducted prior to and after the marketing of oseltamivir are reported on to provide context on the observation of a possible causal association. Fourth, similarity and consistency of toxicity in humans with that in other animals is described. Finally, coherence of toxicokinetic and molecular level of evidence (channels, receptors and enzymes), including differences from the toxicity of other neuraminidase inhibitors, is reviewed. It is concluded that unchanged oseltamivir has various effects on the central nervous system (CNS) that may be related to clinical findings including hypothermia, abnormal behaviours including with fatal outcome, and sudden death. Among receptors and enzymes related to CNS action, it is known that oseltamivir inhibits nicotinic acetylcholine receptors, which are closely related to hypothermia, as well as human monoamine oxidase-A (MAO-A), which is closely related to abnormal or excitatory behaviours. Receptors such as GABAA , GABAB and NMDA and their related receptors/channels including Na+ and Ca2+ channels are thought to be other candidates for investigation related to respiratory suppression followed by sudden death and psychotic reactions (both acute and chronic), respectively.
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PMID:The mechanisms of sudden-onset type adverse reactions to oseltamivir. 2736 59


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