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 present experiments were performed to investigate the effects of the selective mu opioid receptor antagonist, beta-funaltrexamine (beta-FNA), on the physical dependence liability of butorphanol (a mixed agonist/antagonist opioid analgesic). Butorphanol (26 nmol/microliter/h) was continuously infused via osmotic minipumps into the lateral cerebral ventricle of male Sprague-Dawley rats for 72 h. beta-FNA (12, 24, and 48 nmol/5 microliter/rat) was administered ICV 3 h prior to and 48 h after initiation of the butorphanol infusion. Treatment with beta-FNA significantly diminished naloxone-induced escape behavior, hypothermia, and loss of body weight in a dose-dependent manner, while naloxone-induced teeth-chattering, forepaw tremors, and urination were also reduced, but in a dose-independent manner. These results suggest that the mu opioid receptor is partially involved in the development of physical dependence upon butorphanol.
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PMID:Effects of beta-funaltrexamine on butorphanol dependence. 152 43

Butorphanol has been shown to act on mu-, delta-, and kappa-opioid receptors. However, the relative involvement of different opioid receptor subtypes in butorphanol dependence is not known. In the present study, nor-binaltorphimine, a long-acting non-peptide kappa-opioid receptor antagonist, was employed to mask central kappa-opioid receptors before and during the induction of butorphanol dependence in rats, so that the involvement of kappa-opioid receptors could be elucidated. The results revealed that treatment with nor-binaltorphimine markedly blocked naloxone-precipitated withdrawal signs of escape behavior, teeth-chattering, wet shakes, ptosis, body weight loss, and hypothermia at all doses tested, and attenuated the withdrawal symptoms of forepaw tremors (24 nmol: P < 0.001) and diarrhea (12 nmol: P < 0.05; 24 nmol: P < 0.01). In contrast, nor-binaltorphimine had no effect on yawning, ejaculation, nor urination in butorphanol-infused rats undergoing withdrawal. Three days of butorphanol infusion significantly increased KD values (in the cortex and striatum), decreased Bmax (in the cortex only) of [3H]U-69,593 binding, and shifted Ki of nor-binaltorphimine against [3H]U-69,593 (4.5 nM) binding in the cortex by more than 10-fold. Treatment with nor-binaltorphimine blocked the effects of butorphanol on kappa-opioid receptors. It is therefore concluded that kappa-opioid receptors are involved in mediating escape behavior, teeth-chattering, wet shakes, forepaw tremors, ptosis, diarrhea, weight loss, and hypothermia in butorphanol-dependent rats undergoing withdrawal. Furthermore, kappa-opioid receptors become desensitized to agonists (in the cortex and striatum), down-regulated (in the cortex), and supersensitive to antagonists in butorphanol-dependent rats.
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PMID:Effects of nor-binaltorphimine on butorphanol dependence. 822 88

Butorphanol, a synthetic agonist/antagonist, has been shown to act on mu-, delta- and kappa-opioid receptors. However, the relative involvement of opioid receptor subtypes in mediating butorphanol dependence is not known. In the present study, naltrindole, a delta-selective non-peptide antagonist, was administered intracerebroventricularly (i.c.v.) to mask supraspinal delta-opioid receptors before and during the induction of butorphanol dependence. Treatment with naltrindole (0.1, 1, or 10 nmol/5 microliters per rat) significantly blocked naloxone-, a nonspecific antagonist, precipitated butorphanol withdrawal behaviors (escape behavior, teeth-chattering, wet shakes, forepaw tremors, ptosis, diarrhea, body weight loss, and hypothermia) at all doses tested, and decreased ejaculation at 0.1 nmol in butorphanol-infused rats. In contrast, naltrindole treatment had no effect on yawning, nor urination. These results indicate that central delta-opioid receptors are involved in mediating butorphanol dependence in rats.
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PMID:Involvement of delta-opioid receptors in physical dependence on butorphanol. 840 23