title: Evidence that each nerve varicosity on the surface of the mouse vas deferens secretes ATP.
abstract: The secretion of ATP from visualised varicosities on the surface of the mouse vas deferens was determined. Small diameter microelectrodes (about 6 microns and 20 microns) were placed over a set of 2 to 5 varicosities visualised with DiOC2(5) in order to record excitatory junctional currents (e.j.c.s') arising from the evoked secretion of quanta. In high external calcium concentrations, [Ca2+]o, the amplitude-frequency distribution of e.j.c.s' was well described by binomial statistics in which binomial parameter n and the number of varicosities were approximately the same. Idazoxan (1 microM) had no effect on the e.j.c.s' or the binomial parameters p and n. Suramin (100 microM) blocked the e.j.c.s' as well as the spontaneous e.j.c.s' (s.e.j.c.s') in all cases, reducing n and p to zero. These results indicate that all varicosities secrete the transmitter blocked by suramin, presumably ATP.
authors.affiliation: Department of Physiology, University of Sydney, NSW, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Karunanithi
authors.forename: N A
authors.initials: NA
authors.lastname: Lavidis
authors.forename: M R
authors.initials: MR
authors.lastname: Bennett
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D058669:Adrenergic alpha-2 Receptor Antagonists; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D004146:Dioxanes / Q000494:pharmacology; D004594:Electrophysiology; D005071:Evoked Potentials / Q000187:drug effects; D019329:Idazoxan; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008839:Microelectrodes; D009411:Nerve Endings / Q000187:drug effects / Q000378:metabolism; D058919:Purinergic P2 Receptor Antagonists; D013498:Suramin / Q000494:pharmacology; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D014649:Vas Deferens / Q000187:drug effects / Q000294:innervation* / Q000378:metabolism
chemical_list: D058669:Adrenergic alpha-2 Receptor Antagonists; D004146:Dioxanes; D058919:Purinergic P2 Receptor Antagonists; D013498:Suramin; D000255:Adenosine Triphosphate; D002118:Calcium; D019329:Idazoxan