Alpha-adrenoceptor number and function in rat cortex after ethanol and immobilization stress.
Alpha-Adrenoceptor number and function were assessed in rat cortex after ethanol and immobilization stress. Rats subjected to immobilization stress for 2 h/day/7 days showed a significant reduction in alpha 2-adrenoceptors in cortex ( [3H]clonidine binding) but no change in alpha 1-adrenoceptors ( [3H]prazosin binding). The inhibitory effect of clonidine (500 nM) on 3H efflux from cortical slices preincubated with [3H]norepinephrine was reversed in the stressed animals. These effects on alpha 2-adrenoceptor number and function were reduced when stress was accompanied by chronic administration of ethanol (35% of calories in a liquid diet) although when given alone ethanol produced small changes in the same direction as those produced by stress. It is suggested that, in its effects on cortical alpha-adrenoceptors, chronic ethanol administration attenuates the effects of severe stress though itself perhaps acting as a mild stressor when given as part of a liquid diet regimen.
D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects / Q000502:physiology* / Q000503:physiopathology; D003000:Clonidine / Q000378:metabolism; D000431:Ethanol / Q000494:pharmacology*; D006801:Humans; D008297:Male; D009638:Norepinephrine / Q000378:metabolism; D011224:Prazosin / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects / Q000502:physiology*; D013315:Stress, Psychological / Q000503:physiopathology*
D011942:Receptors, Adrenergic, alpha; D000431:Ethanol; D003000:Clonidine; D009638:Norepinephrine; D011224:Prazosin