title: Functional pattern of sacral root stimulation: III. Erection.
abstract: The mechanism of canine penile erection was studied in 6 'chronic' and 15 'acute' male dogs by means of sacral root stimulation combined with pharmacologic studies. The basic mechanism of erection cannot be explained by a pure increase in arterial perfusion of the cavernous spaces due to neural vasomotor regulation. The vasomotor mechanism, whether pure arteriolar vasodilation, or venous drainage impairment, or secondary to as yet undefined behavior of the corporal smooth muscle, can be activated by stimulation of the parasympathetic outflow. Those preganglionic fibers may synapse to noncholinergic and non-beta-adrenergic neurons, which release a yet unidentified vasodilator neurotransmitter mediating the neurovascular effect.
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D003864:Depression, Chemical; D004285:Dogs; D004558:Electric Stimulation; D004837:Epinephrine / Q000494:pharmacology; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D010410:Penile Erection / Q000187:drug effects; D010646:Phentolamine / Q000494:pharmacology; D011413:Propantheline / Q000494:pharmacology; D012445:Sacrococcygeal Region / Q000187:drug effects / Q000502:physiology; D013126:Spinal Nerve Roots / Q000187:drug effects / Q000502:physiology*; D013726:Terbutaline / Q000494:pharmacology; D014294:Trimethaphan / Q000494:pharmacology
chemical_list: D011413:Propantheline; D014294:Trimethaphan; D007545:Isoproterenol; D013726:Terbutaline; D004837:Epinephrine; D010646:Phentolamine