ABSTRACT
It is generally assumed that the neurotransmitter 5–hydroxytryptamine (5–HT, serotonin) has an inhibitory role in the mediation of male rat sexual behaviour. This assumption is based on the observation that an increase in brain 5–HT, as produced by inhibitors of monoamine oxidase or the 5–HT precursor, 5–hydroxytryptophan (5–HTP), is accompaned by an inhibition of the behaviour. Conversely, a decrease in brain 5–HT, as produced by the inhibition of tryptophan hydroxylase by p–chloro–phenylalanine (PCPA), chemical or mechanical lesions of 5–HT neurons, facilitates male rat sexual behaviour. The experimental evidence has been summarized in a number of recent reviews (e.g. Meyerson and Malmnäs, 1978; Crowley and Zemlan, 1981; Larsson and Ahlenius, 1985; Bitran and Hull, 1987). In this presentation we will focus on results obtained by means of the new serotonergic agent 8–OH–2–(di–n–propylamino) tetralin (8–OH–DPAT) (Arvidsson et al., 1981).
