RESUMO
In an attempt to define the nature of the involvement of delta 9-tetrahydrocannabinol (THC) with central cholinergic neurotransmission, the effects of THC on direct cholinergic stimulation of the rat brain were investigated. THC, in doses of 3 mg/kg and 6 mg/kg, administered intraperitoneally (i.p.), potentiated the effects of carbachol injection into the lateral septal nucleus, as manifested by enhancement of the drinking response elicited by the septal carbachol injection and by potentiation of the tendency of this carbachol injection to induce abnormal motor responses. Although atropine (10 mg/kg, i.p.) completely blocked the carbachol induced drinking, the atropine did not completely block the drinking response when THC was given with carbachol. The results indicate an apparent sensitization, by THC, of a limbic cholinergic system.
Assuntos
Encéfalo/efeitos dos fármacos , Carbacol/farmacologia , Dronabinol/farmacologia , Acetilcolina/fisiologia , Animais , Atropina/farmacologia , Carbacol/administração & dosagem , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Dronabinol/administração & dosagem , Sinergismo Farmacológico , Injeções , Injeções Intraperitoneais , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Convulsões/induzido quimicamente , Núcleos Septais/efeitos dos fármacosAssuntos
Cannabis/farmacologia , Circulação Cerebrovascular/efeitos dos fármacos , Dronabinol/farmacologia , Animais , Gânglios da Base/irrigação sanguínea , Comportamento Animal/efeitos dos fármacos , Tronco Encefálico/irrigação sanguínea , Débito Cardíaco/efeitos dos fármacos , Cerebelo/irrigação sanguínea , Córtex Cerebral/irrigação sanguínea , Estado de Consciência/fisiologia , Depressão Química , Hipocampo/irrigação sanguínea , Hipotálamo/irrigação sanguínea , Masculino , RatosRESUMO
Young growing rats were maintained on a magnesium deficient diet, and injected with ketamine after 7, 11, 14, and 18 days on the diet. A comparison of the sleeping times, as measured by the loss of the righting reflex after injections of three doses of ketamine, was made with rats similarly maintained on a control diet. Tolerance with successive injections to ketamine, indicated by a decrease in sleeping time, was noted only among the control rats. After 14 and 18 days on the diet, the magnesium deficient rats showed no tolerance to the earlier injections, but their sleeping times were longer than their control counterparts. In rats injected for the first time on day 14 of the diet, the magnesium deficient rats showed significantly longer sleeping times than the control rats; this suggests that the difference in sleeping times between groups is not entirely dependent upon the development of tolerance to the drug seen in the control rats. In addition, a sex difference was noted, with female rats sleeping longer with ketamine than male rats.
