Enhancement effects of nicotine on neurogenic relaxation responses in the corpus cavernosum in rabbits: The role of nicotinic acetylcholine receptor subtypes


ÖZTÜRK FİNCAN G. S. , Vural I. M. , Ercan Z. S. , Sarioglu Y.

EUROPEAN JOURNAL OF PHARMACOLOGY, vol.627, pp.281-284, 2010 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 627
  • Publication Date: 2010
  • Doi Number: 10.1016/j.ejphar.2009.10.042
  • Journal Name: EUROPEAN JOURNAL OF PHARMACOLOGY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.281-284
  • Keywords: Nicotine, Nicotinic acetylcholine receptor subtype, Corpus cavernosum, (Rabbit), NORADRENALINE RELEASE, CONTRACTILE RESPONSES, PELVIC GANGLION, RAT, STIMULATION, NEURONS, SUBUNIT, MECHANISM, CHOLINE
  • Gazi University Affiliated: Yes

Abstract

Nicotine acts as an agonist of nicotinic acetylcholine receptors, which belong to a superfamily of neurotransmitter-gated ion channels. We previously demonstrated that nicotine increases the electrical field stimulation (EFS)-evoked nitrergic relaxation responses via activation of nicotinic acetylcholine receptors. The aim of the present study is to investigate the subtypes of nicotinic acetylcholine receptors in rabbit corpus cavernosum. EFS-evoked relaxation responses were recorded from corpus cavernosum strips obtained from rabbits with an isometric force displacement transducers. Effects of nicotine on EFS-evoked relaxations were examined in pre-contracted tissues. Then the effect of nicotine on the EFS-evoked relaxations was examined in the presence of hexamethonium, dihydro-beta-erythroidine, mecamylamine or alpha-bungarotoxin. In our study, nicotine (3 x 10(-5), 10(-4)) transiently increased nitrergic relaxations induced by EFS in the rabbit isolated corpus cavernosum. While hexamethonium and mecamylamine near totally inhibited or abolished the neurorelaxation response to nicotine (3 x 10(-5)) on EFS, dihydro-beta-erythroidine and alpha-bungarotoxin partially inhibited these responses. These findings demonstrated that the alpha3-beta4, alpha4-beta2 and alpha7 subunits of nicotinic acetylcholine receptors play role on the nicotine-induced augmentation in EFS-evoked relaxation responses in rabbit corpus cavernosum. (C) 2009 Elsevier B.V. All rights reserved.