title: Glutamatergic transmission is involved in the long lasting sexual inhibition of sexually exhausted male rats.
abstract: Copulation to satiation induces a series of enduring physiological changes in male rats, with the appearance of a long lasting sexual inhibitory period as the most conspicuous, that are suggestive of the occurrence of neuroplastic changes. Copulation is a natural reward activating the mesocorticolimbic circuit and inducing nucleus accumbens dopamine release. The repeated activation of this system by drug rewards induces neuroplastic changes involving both dopamine and glutamate transmission. We hypothesized that repeated activation of the mesocorticolimbic circuit during copulation to satiation might also activate these neurotransmitter systems. The objective of the present work was to establish the possible participation of glutamate transmission in sexual satiety. To this aim we tested if the systemic injection of specific glutamate receptor antagonists of the NMDA, AMPA and mGluR5 receptor subtypes would reverse the sexual inhibitory state characteristic of sexually satiated rats. Results showed that systemic administration of low doses of the three glutamate receptor antagonists reversed sexual exhaustion evidencing a role for glutamate in the maintenance of the sexual inhibition that follows copulation to satiation, with the participation of NMDA, AMPA and mGluR5 receptors. These glutamate receptor subtypes have been associated to the neuroplastic changes resulting from repeated activation of the mesocorticolimbic circuit by drug rewards, a phenomenon that might also result from its activation by continued copulation.
authors: Departamento de Farmacobiología, Cinvestav-Sede Sur, Calzada de los Tenorios 235, Col. Granjas Coapa, Delegación Tlalpan 14330 D.F., Mexico. Electronic address: grodrigu@cinvestav.mx.
authors: Gabriela
authors: G
authors: Rodríguez-Manzo
mesh_terms: D000818:Animals; D003307:Copulation / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004542:Ejaculation / Q000187:drug effects / Q000502:physiology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005260:Female; D018698:Glutamic Acid / Q000502:physiology*; D008297:Male; D016202:N-Methylaspartate / Q000494:pharmacology; D018377:Neurotransmitter Agents / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D064529:Receptor, Metabotropic Glutamate 5 / Q000037:antagonists & inhibitors; D012528:Satiety Response / Q000187:drug effects; D012726:Sexual Behavior, Animal / Q000187:drug effects / Q000502:physiology*; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*; D013997:Time Factors; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology
chemical_list: D018691:Excitatory Amino Acid Antagonists; C578937:Grm5 protein, rat; D018377:Neurotransmitter Agents; D064529:Receptor, Metabotropic Glutamate 5; D018698:Glutamic Acid; D016202:N-Methylaspartate; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid
keywords: Glutamate; NMDA, AMPA and mGluR5 receptors; Neuroplastic changes; Sexual behavior expression; Sexual satiety