title: Phenotype-specific down-regulation of nicotinic acetylcholine receptors in the pelvic ganglia of castrated rats: implications for neurogenic erectile dysfunction.
abstract: Pelvic ganglia (PG) play critical roles in relaying sympathetic and parasympathetic information from the spinal cord to the penile vasculature and, controlling the penile reflex. Animal studies have shown that androgen deprivation by castration causes erectile dysfunction (ED). Until now, however, neural mechanisms underlying castration-induced ED remain unclear. Therefore, we examined whether androgen deprivation down-regulates nicotinic acetylcholine receptors (nAchRs), which mediate fast excitatory synaptic transmission in the PG. Toward this end, neurogenic ED was demonstrated by measuring the intracavernous pressure in castrated rats. Real-time PCR analysis revealed that the transcripts encoding nAchR α3/α5/β4 subunits were significantly down-regulated in the PG neurons. In addition, down-regulation of the nAchR subunits was reversed by replacement of testosterone. Patch-clamp experiments showed that the nAchR currents were selectively attenuated in the parasympathetic PG neurons innervating the penile vasculature, activation of which elicits penile erection. Taken together, our data suggest that phenotype-specific down-regulation of nAchRs in the PG neurons may contribute to the neurogenic ED in castrated rats.
authors.affiliation: Department of Anesthesiology, The Affiliated Hospital of Yanbian University, Yanji 133000 Yanji, China.
authors.forename: Xue-Zhu
authors.initials: XZ
authors.lastname: Huang
authors.forename: Jong-Taek
authors.initials: JT
authors.lastname: Park
authors.forename: Han-Gyu
authors.initials: HG
authors.lastname: Kim
authors.forename: Choong-Ku
authors.initials: CK
authors.lastname: Lee
authors.forename: Yu-Jin
authors.initials: YJ
authors.lastname: Won
authors.forename: Byong-Gon
authors.initials: BG
authors.lastname: Park
authors.forename: Seong-Woo
authors.initials: SW
authors.lastname: Jeong
mesh_terms: D000818:Animals; D015536:Down-Regulation; D007172:Erectile Dysfunction / Q000209:etiology / Q000235:genetics / Q000378:metabolism; D005726:Ganglia, Parasympathetic / Q000378:metabolism*; D005728:Ganglia, Sympathetic / Q000378:metabolism*; D008297:Male; D009919:Orchiectomy; D010388:Pelvis / Q000294:innervation*; D010410:Penile Erection / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011978:Receptors, Nicotinic / Q000235:genetics* / Q000378:metabolism
chemical_list: D011978:Receptors, Nicotinic