Evidence that nitric oxide modulates drinking behaviour.

G Calapai; F Squadrito; D Altavilla; B Zingarelli; G M Campo; M Cilia; A P Caputi

doi:10.1016/0028-3908(92)90038-q

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Evidence that nitric oxide modulates drinking behaviour.

G Calapai·F Squadrito·D Altavilla·B Zingarelli·G M Campo·M Cilia·A P Caputi

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Abstract

The involvement of the L-arginine-nitric oxide (NO) pathway in brain, in the regulation of drinking behaviour, has been evaluated by injecting L-arginine and N omega-nitro-L-arginine methyl ester (L-NAME) into the lateral cerebral ventricle (i.c.v.). L-Arginine (5 and 10 micrograms/rat), but not D-arginine, was antidipsogenic when administered to 24 hr water-deprived rats but did not change the intake of water in normally hydrated rats. However, L-NAME (5 and 10 micrograms/rat) did antagonize the effect of L-arginine in water-deprived animals but, by itself, did not increase thirst. L-Arginine (100 ng), when injected into the preoptic area significantly reduced water deprivation-induced drinking. The same dose was unaffective when given intraventricularly. Finally, L-arginine (5 and 10 micrograms/rat, i.c.v.) inhibited drinking induced by intraventricular injection of angiotensin II (250 ng/rat). The effect was dose-dependent. The results indicate that: (1) NO acts as an inhibitory mechanism when thirst is stimulated by water deprivation or by angiotensin II; (2) the preoptic area might be one of the central sites of antidipsogenic action of NO and (3) nitric oxide synthase might be inhibited during water deprivation.

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Angiotensin II Animals Arginine Drinking Behavior Drug Synergism Injections Injections, Intraventricular Male NG-Nitroarginine Methyl Ester Nitric Oxide Preoptic Area Rats Rats, Inbred Strains Stereoisomerism Water Deprivation Journal Article Research Support, Non-U.S. Gov't

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G Calapai, F Squadrito, D Altavilla, B Zingarelli, G M Campo, M Cilia, A P Caputi. 1992. Evidence that nitric oxide modulates drinking behaviour.. https://doi.org/10.1016/0028-3908(92)90038-q

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