Dopamine is involved in the different patterns of copulatory behaviour of Roman high and low avoidance rats: studies with apomorphine and haloperidol.

摘要: Outbred Roman high- (RHA) and low-avoidance (RLA) rats, originally selected for rapid vs. poor acquisition of active avoidance in a shuttle box, show differential copulatory patterns when exposed to receptive female. Indeed, the first copulation test male RHA rats more mounts, intromissions ejaculations than RLA rats. Such differences do not disappear subsequent tests, with sexually experienced always showing higher levels sexual motivation performance their counterparts. This study shows that different are differentially facilitated by apomorphine, mixed D1/D2-like dopamine receptor agonist, impaired haloperidol, D2-like antagonist, given at doses which facilitate impair, respectively, behaviour Sprague Dawley used as an external reference strain. Accordingly, apomorphine-induced facilitation haloperidol-induced impairment were robust indicated effects on several parameters including mount, intromission ejaculation latencies, frequencies, post ejaculatory interval, inter-intromission interval efficacy. Pretreatment haloperidol also reduced facilitatory effect apomorphine effectively These results suggest mainly due lower dopaminergic tone level mesolimbic incerto-hypothalamic systems play key role behaviour.