Open Accessp ‐Chloroamphetamine‐induced rat ejaculation is not associated with the preoptic nucleus or medial nucleus amygdala
Author(s) -
YOKOSUKA MAKOTO,
TAKAGI SHUNSUKE,
KATOU MASAHIRO,
PUDCHARAPORN KROMKHUM,
GIZURARSON SVEINBJORN,
ICHIKAWA MASUMI,
SAITO TORU R.
Publication year - 2008
Publication title -
reproductive medicine and biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.005
H-Index - 22
eISSN - 1447-0578
pISSN - 1445-5781
DOI - 10.1111/j.1447-0578.2007.00199.x
Subject(s) - ejaculation , p chloroamphetamine , nucleus , amygdala , estrous cycle , medicine , endocrinology , neuroscience , chemistry , serotonergic , biology , serotonin , receptor
Aim: In the rat, intraperitoneal injection of p ‐chloroamphetamine (PCA), which releases central 5‐hydroxytryptamine (5‐HT) from serotonergic nerve terminals, induces ejaculation, even in the absence of an estrus female or female‐related smell information. It is well known that the medial preoptic nucleus (MPN) and the medial nucleus amygdala (MEA) play a major role in the control of male sexual behavior in mammals. We examined whether or not neuronal activity of the MPN and/or the MEA was associated with PCA‐induced ejaculation. Methods: Using c‐Fos immunohistochemistry, we demonstrated a difference in the neural activities of the MPN and the MEA for ejaculation during copulation with an estrus female and ejaculation by PCA injection. Results: Increased numbers of c‐Fos‐immunoreactive (c‐Fos‐IR) cells were found in the MPN and the MEA in the brains of the mating animals, whereas in the brains of the animals undergoing PCA‐induced ejaculation there was no increase in the number of c‐Fos‐IR cells in the MPN and a small increase in the MEA. Conclusion: Based on these results, ejaculation induced by PCA is not associated with the MPN. Moreover, the MEA is not the main act for this ejaculation. (Reprod Med Biol 2008; 7 : 37–43)