Antipyretic effect of central arginine8-vasopressin treatment: V1 receptors specifically involved?
Intracerebroventricular (i.c.v.) administration of the neurohypophyseal neuropeptide arginine8-vasopressin (AVP) results in a dose-dependent attenuation of endotoxin-induced fever (EIF) in rats. Specific antagonists of the neuropeptided(CH2)5[Tyr(Me)2]AVP for V1 receptors, d(CH2)5[dlle2lle4]AVP for the V2 receptors and Des-Gly,NH2d(CH2)5[Tyr)Me2)Thr4Orn8]vasotocin, an antagonist of the oxytocin receptors (AOXT), failed to modify EIF when administered i.c.v. Relatively high doses (100 ng) of all three peptide antagonists effectively blocked the antipyretic effect of AVP. Administered in smaller doses (10 or 30 ng), however, a more specific interaction was observed, i.e. the V1 antagonist being the only effective compound in preventing the effect of AVP. Although the data indicate that peptide-antagonist interactions should be interpreted carefully, the present experiments confirm previous observations on the involvement of V1-type receptors in the antipyretic action of AVP and suggest additional interactions with V2 vasopressinergic and oxytocinergic receptors.
Kovacs
G L
GL
Rudolf Magnus Institute for Pharmacology, University of Utrecht, The Netherlands.
Baars
A M
AM
De Wied
D
D
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D001127:Arginine Vasopressin / Q000494:pharmacology*; D004731:Endotoxins / Q000494:pharmacology*; D006979:Hyperthermia, Induced; D008297:Male; D010121:Oxytocin / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011945:Receptors, Angiotensin / Q000187:drug effects*; D018045:Receptors, Oxytocin; D017483:Receptors, Vasopressin; D014667:Vasopressins / Q000378:metabolism
D000894:Anti-Inflammatory Agents, Non-Steroidal; D004731:Endotoxins; D011945:Receptors, Angiotensin; D018045:Receptors, Oxytocin; D017483:Receptors, Vasopressin; D014667:Vasopressins; D001127:Arginine Vasopressin; D010121:Oxytocin