title: The atrial receptors responsible for the decrease in plasma vasopressin caused by distension of the left atrium in the dog.
abstract: In dogs anaesthetized with chloralose, the effects of cooling the cervical vagi on the reflex decrease in plasma concentration of vasopressin, caused by distension of a large balloon in the lumen of the left atrium, were examined. Distension of the balloon in ten dogs with the vagi at 37 degrees C resulted in a decrease in plasma concentration of vasopressin and, as before, an increase in urine flow. The responses were not significantly affected by cooling to 16-18 degrees C but were abolished at 9 degrees C. At 16-18 degrees C the increase in activity in myelinated vagal afferent fibres is largely unchanged and at 9 degrees C is abolished (Kappagoda, Linden & Sivananthan, 1979; Sivananthan, Kappagoda & Linden, 1981). It is concluded that the decrease in plasma concentration of vasopressin during distension of the left atrium is mediated by the Paintal-type atrial receptors with myelinated vagal afferent fibres.
mesh_terms: D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D003080:Cold Temperature; D004285:Dogs; D006325:Heart Atria / Q000294:innervation*; D009412:Nerve Fibers / Q000502:physiology*; D011311:Pressoreceptors / Q000502:physiology*; D012018:Reflex / Q000502:physiology; D014630:Vagus Nerve / Q000502:physiology; D014667:Vasopressins / Q000097:blood*
chemical_list: D014667:Vasopressins