Interactive effects of brain catecholamines and variations in sexual and non-sexual arousal on copulatory behavior of male rats.
In pargyline pretreated male rats, an intraventricular 6-hydroxydopamine procedure which resulted in subtotal brain catecholamine (CA) depletion produced a mild defict in copulatory behavior followed by rapid recovery. Challenges employed to study the behavioral capacities of these 'recovered' animals revealed: (1) a heightened sensitivity to acute treatment with the CA synthesis inhibitor alpha-methyl tyrosine (AMT) as reflected in a reinstatement and exaggeration of the original copulation deficit; (2) a greater dependence on the sexual eliciting properties of the female, since abolishing her soliciting behavior also reinstated and exaggerated the sexual dysfunction; and (3) a pattern of behavioral impairment indicating increased difficulty in both initiating sexual activity and maintaining copulatory performance. Furthermore, in males not copulating after 6-OHDA/AMT treatment, copulation could easily be induced by the simple application of a non-specific activating stimulus. On the basis of these data and parallel findings reported for other behaviors, we have concluded that: (1) both the initiation and maintenance of copulatory behavior in the male rat is the part dependent on normal functioning in one or more of the brain CA-containing systems; and (2) this copulatory deficit is symptomatic of a broader functional impairment reflecting reduced behavioral responsiveness to stimuli that normally elict appetitive or approach responses but not to stimuli requiring more automatic, inhibitory responses.
D000818:Animals; D001921:Brain / Q000502:physiology*; D002395:Catecholamines / Q000502:physiology*; D002421:Caudate Nucleus / Q000378:metabolism; D002540:Cerebral Cortex / Q000378:metabolism; D003307:Copulation / Q000502:physiology*; D004298:Dopamine / Q000378:metabolism; D004542:Ejaculation / Q000187:drug effects; D005260:Female; D006220:Haloperidol / Q000494:pharmacology; D006892:Hydroxydopamines / Q000494:pharmacology; D007031:Hypothalamus / Q000378:metabolism; D008297:Male; D008781:Methyltyrosines / Q000494:pharmacology; D009638:Norepinephrine / Q000378:metabolism; D010293:Pargyline / Q000494:pharmacology; D051381:Rats; D012726:Sexual Behavior, Animal / Q000502:physiology
D002395:Catecholamines; D006892:Hydroxydopamines; D008781:Methyltyrosines; D010293:Pargyline; D006220:Haloperidol; D004298:Dopamine; D009638:Norepinephrine