title: [Effects of central and peripheral administration of a nitric oxide synthase inhibitor on AVP-induced hypothermia in rats].
abstract: OBJECTIVE
  To explore the role of nitric oxide (NO) in arginine vasopressin (AVP)-induced hypothermia.
  
  
  METHODS
  Colonic temperature was measured at 30 min intervals with a digital thermometer. Effects of central and peripheral administration of nitric oxide synthase (NOS) inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) on AVP-induced hypothermia were observed in rats.
  
  
  RESULTS
  (1) Intravenous injection (i.v.) of AVP (4 microg x kg(-1)) and L-NAME (30 mg x kg(-1)) produced a significant drop in body temperature, respectively. Coadministration of L-NAME i.v. with AVP i.v. did not significantly influence the magnitude of AVP-induced hypothermia. (2) Intracerebroventricular (i.c.v.) injection of L-NAME (1 mg x kg(-1)) caused a significant increase in body temperature, but when the treatments with AVP and L-NAME were combined, i.c.v. injection of L-NAME markedly blocked the hypothermic effect of AVP intravenous injection.
  
  
  CONCLUSIONS
  Endogenous NO in the central nervous system plays a major role in AVP-induced hypothermia. In addition, central NO seems to play a tonic thermoregulatory role by reducing normal body temperature because an increase in body temperature was observed after treatment with NOS inhibitor L-NAME.
authors.affiliation: Lanzhou Military Medical College of PLA, Lanzhou 730020, China.
authors.forename: Yong-Lu
authors.initials: YL
authors.lastname: Yang
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yang
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Li
authors.forename: Yu-Shan
authors.initials: YS
authors.lastname: Li
authors.forename: Xiao-Hong
authors.initials: XH
authors.lastname: Luo
mesh_terms: D000818:Animals; D001127:Arginine Vasopressin / Q000494:pharmacology*; D001831:Body Temperature / Q000187:drug effects*; D001833:Body Temperature Regulation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D007035:Hypothermia / Q000139:chemically induced*; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology*; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D004791:Enzyme Inhibitors; D001127:Arginine Vasopressin; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D019331:NG-Nitroarginine Methyl Ester