title: P2X2 receptor expression by interstitial cells of Cajal in vas deferens implicated in semen emission.
abstract: Male reproduction is dependent upon seminal emission mediated by vas deferens contraction. This drives spermatic fluid to the prostatic urethra during ejaculation. We localize interstitial cells of Cajal (ICC), which express P2X2 receptor, subunits of ATP-gated ion channels, to rat, mouse and guinea-pig vas deferens submucosa. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of rat vas deferens resolved two functional splice variant transcripts of the P2X2 receptor subunit. The P2X2 receptor mRNA was localized principally within the lamina propria (submucosal) region of the rat vas deferens using in situ hybridization (ISH) and in situ RT-PCR-ISH. Immunohistochemistry using rat, mouse and guinea-pig vas deferens tissues confirmed expression of P2X2 receptor protein within the lamina propria, particularly within a dense column of small spindle-shaped cells adjacent to the columnar epithelial cells which line the lumen. This immunoreactivity was co-localized with neurone-specific enolase (NSE) and c-Kit protein expression, gene markers for ICC. Mucosal mast cells were distinguished from ICC by toluidine blue staining. Choline acetyltransferase immunoreactivity, a marker for post-ganglionic parasympathetic innervation, occurred on the lateral margin of the lamina propria and extended into the inner longitudinal muscle layer. P2X1 receptor immunolabelling was associated with sympathetic innervation of the smooth muscle in the outer longitudinal and circular muscle layers, but not the inner longitudinal layer. The physiological significance of the vas deferens ICC which express P2X2 receptors remains to be established. Possible roles include regulation of smooth muscle activity or mucosal secretion utilizing local ATP signaling, both of which would affect semen transport.
authors: Department of Physiology, Faculty of Medicine and Health Sciences, University of Auckland, New Zealand.
authors: L D
authors: LD
authors: Burton
authors: G D
authors: GD
authors: Housley
authors: S G
authors: SG
authors: Salih
authors: L
authors: L
authors: Järlebark
authors: D L
authors: DL
authors: Christie
authors: D
authors: D
authors: Greenwood
mesh_terms: D000165:Acridine Orange; D000255:Adenosine Triphosphate / Q000502:physiology; D000344:Afferent Pathways / Q000033:anatomy & histology / Q000502:physiology; D017398:Alternative Splicing; D000818:Animals; D015415:Biomarkers; D004396:Coloring Agents; D004542:Ejaculation / Q000502:physiology*; D005786:Gene Expression Regulation; D006168:Guinea Pigs; D007124:Immunoenzyme Techniques; D017403:In Situ Hybridization; D008297:Male; D051379:Mice; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D009119:Muscle Contraction; D009130:Muscle, Smooth / Q000294:innervation / Q000502:physiology; D010751:Phosphopyruvate Hydratase / Q000032:analysis; D021122:Protein Subunits; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D018048:Receptors, Purinergic P2 / Q000096:biosynthesis* / Q000235:genetics; D058476:Receptors, Purinergic P2X2; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013045:Species Specificity; D013194:Staining and Labeling; D013564:Sympathetic Nervous System / Q000033:anatomy & histology / Q000502:physiology; D014048:Tolonium Chloride; D014649:Vas Deferens / Q000166:cytology* / Q000378:metabolism
chemical_list: D015415:Biomarkers; D004396:Coloring Agents; C546402:P2rx2 protein, mouse; C546403:P2rx2 protein, rat; D021122:Protein Subunits; D012333:RNA, Messenger; D018048:Receptors, Purinergic P2; D058476:Receptors, Purinergic P2X2; D014048:Tolonium Chloride; D000255:Adenosine Triphosphate; D010751:Phosphopyruvate Hydratase; D000165:Acridine Orange