J Korean Androl Soc.  1996 Jun;14(1):3-8.

Relation between Neurotransmitters of the Central Nervous System Involved in Male Sexual Function

• Song YS
• Lee SH
• Choi HK
• Ahn YS

Abstract

5-Hydroxytryptamine (5-HT)-containing pathways in the central nervous system (CNS) exert a general inhibitory effect on erection, whereas dopamine appears to have a facilitatory effect. The reaction of serotomin to changes in dopamine in the CNS is not known. We examined the relation between dopamine and serotonin in 400-mum slices of the rat hippocampus. After 30 minutes incubation in normal buffer, the slices were incubated for 20 minutes in a buffer containing [3H]5-HT and then washed. After administration of dopamine, the release of 3H into the buffer was measured, and the radioactivities in each buffer and the tissue were measured. The results were expressed as a percentage of the total activity. Spontaneous release of [3H]5-HT decreased rapidly during the first 40 minutes of incubation. Through the rapid release of [3H]5-HT, a steady state was obtained by 50 minutes of incubation. The pattern of [3H]5-HT release in the presence of tetrodotoxin (10-6 M) alone was similar to that of the control tissue slices. The release of [3H]5-HT was significantly increased after administration of dopamine (10-5 M), and this response was not blocked by tetrodotoxin. These results suggest that in the region of the CNS involved in male sexual function, dopamine increases the release of serotonin by acting directly on serotonergic nerve fibers.

MeSH Terms

Animals
Central Nervous System*
Dopamine
Hippocampus
Humans
Male*
Nerve Fibers
Neurotransmitter Agents*
Penile Erection
Radioactivity
Rats
Serotonin
Tetrodotoxin
Dopamine
Neurotransmitter Agents
Serotonin
Tetrodotoxin