Reorganization of the innervation of the vas deferens after sympathetic decentralization

Reorganization of autonomic efferent pathways to the rat vas deferens was noted after chronic (30 days) sympathetic decentralization produced by hypogastric nerve (HGN) transection. In normal rats, electrical stimulation of the HGN elicited an increase in vasal pressure (VP) bilaterally, whereas pelvic nerve (PN) stimulation did not alter VP. However, after unilateral HGN transection, stimulation of the PN on the transected side but not on the normal side increased VP. The decentralized vas exhibited larger VP responses to stimulation of the contralateral HGN in comparison with the normal vas. After bilateral HGN transection, PN-induced VP responses were elicited at lower stimulus intensities than in rats with unilateral transections. PN-induced VP responses were blocked by hexamethonium and prazosin but were not altered by atropine. Distension of the vas lumen occurred after decentralization. PN-induced VP responses were not detectable in extremely distended vas. These data indicate that, after degeneration of sympathetic preganglionic axons, decentralized adrenergic ganglion cells are reinnervated by parasympathetic or sympathetic preganglionic pathways and that the reinnervation influences vasal function.