Inhibitory effect of gaseous neuromodulators in vasopressin and oxytocin release induced by endotoxin in rats.
Nitric oxide (NO) and carbon monoxide (CO) are endogenously synthesized gaseous molecules that act as neurotransmitters in central nervous system. In this study we investigated the modulatory role of NO and CO in lipopolysaccharide (LPS)-induced vasopressin and oxytocin secretion. Intracerebroventricular (i.c.v.) injection of N omega-L-nitro-arginine methyl ester (L-NAME), 3-morpholino-sydnonimine (SIN-1), zinc deuteroporphyrin 2,4-bis glicol (ZnDPBG) or hemin did not change the basal vasopressin and oxytocin plasma levels. After endovenous LPS administration, plasma vasopressin and oxytocin increased, reaching a peak at 60 min, and returning to basal levels afterwards. LPS administration induced a higher vasopressin and oxytocin plasma levels in rats previously treated with L-NAME and ZnDPBG (P<0.05) compared to rats pre-treated with vehicle. On the other hand, in rats previously treated with SIN-1 or hemin, there was a significant reduction in the vasopressin and oxytocin secretion. These findings confirm the inhibitory role of NO and CO in the LPS-induced vasopressin and oxytocin secretion.
Giusti-Paiva
Alexandre
A
Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, 14049-900 Ribeirão Preto, São Paulo, Brazil.
Elias
Lucila Leico Kagohara
LL
Antunes-Rodrigues
José
J
D000818:Animals; D002248:Carbon Monoxide / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006419:Heme Oxygenase (Decyclizing) / Q000187:drug effects / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D018377:Neurotransmitter Agents / Q000494:pharmacology*; D009569:Nitric Oxide / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000187:drug effects / Q000378:metabolism; D010121:Oxytocin / Q000096:biosynthesis / Q000097:blood / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D014667:Vasopressins / Q000096:biosynthesis / Q000097:blood / Q000187:drug effects*
D004791:Enzyme Inhibitors; D008070:Lipopolysaccharides; D018377:Neurotransmitter Agents; D014667:Vasopressins; D009569:Nitric Oxide; D010121:Oxytocin; D002248:Carbon Monoxide; D019001:Nitric Oxide Synthase; D006419:Heme Oxygenase (Decyclizing)