Dopamine D2-like receptor agonists induce penile erection in male rats: differential role of D2, D3 and D4 receptors in the paraventricular nucleus of the hypothalamus

► Dopamine agonists apomorphine and pramipexole induce penile erection in rats/humans. ► One brain site of action is the paraventricular nucleus of the hypothalamus (PVN). ► Selective D2, but not D3 or D4 antagonists reduce drug-induced pro-erectile effect. ► PVN D2 receptors play a main role in the pro-erectile effect of these drugs. ► However, the selective stimulation of PVN D4 receptors induces penile erection.