Nitric oxide promotes medial preoptic dopamine release during male rat copulation.
Dopamine (DA) is released in the medial preoptic area (MPOA) of male rats during copulation. DA agonists infused into the MPOA facilitate, and antagonists impair, copulatory behavior. Local administration of the nitric oxide (NO) precursor L-arginine also increases DA release in the MPOA. The present experiment used microdialysis to test whether NO promotes DA release during copulation. Males received either an NO synthesis inhibitor, nitro-L-arginine methyl ester (L-NAME, 400 microM), or its inactive isomer D-NAME (400 microM) into the MPOA via a microdialysis probe for 3 h prior to the introduction of a female. Following D-NAME administration, DA increased during copulation, while L-NAME prevented this increase. NO may therefore promote DA release in the MPOA of male rats, thereby facilitating copulation.
Lorrain
D S
DS
Department of Psychology, State University of New York at Buffalo 14260, USA.
Matuszewich
L
L
Howard
R V
RV
Du
J
J
Hull
E M
EM
D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003307:Copulation / Q000502:physiology*; D004298:Dopamine / Q000378:metabolism*; D004563:Electrochemistry; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005110:Extracellular Space / Q000187:drug effects / Q000378:metabolism; D005260:Female; D006719:Homovanillic Acid / Q000378:metabolism; D008297:Male; D017551:Microdialysis; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D011301:Preoptic Area / Q000187:drug effects / Q000378:metabolism*; D051381:Rats
D004791:Enzyme Inhibitors; D015102:3,4-Dihydroxyphenylacetic Acid; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D019331:NG-Nitroarginine Methyl Ester; D004298:Dopamine; D006719:Homovanillic Acid