AJP - Regulatory, Integrative and Comparative Physiology, Vol 245, Issue 3 311-R320, Copyright © 1983 by American Physiological Society
Upper thoracic sympathetic neuron responses to input from urinary bladder afferents
R. Schondorf, W. Laskey and C. Polosa
The aim of the present study was to evaluate the organization of neural
circuitry responsible for the intersegmental transmission of input from
urinary bladder afferents to sympathetic preganglionic neurons (SPNs). The
electrical activity of SPNs was recorded from axons of the cervical
sympathetic trunk in anesthetized central nervous system (CNS)-intact and
in unanesthetized midcollicular-decerebrate or acute C1 spinal cats. In all
three preparations, tonically active SPNs were excited or inhibited by 1)
electrical stimulation of myelinated afferents of the pelvic or hypogastric
nerve, both of which contain bladder afferents, and 2) spontaneous
contraction or distension of the urinary bladder. The SPN responses to
bladder distension were abolished by pelvic nerve section. A comparison of
responses of SPNs in CNS-intact and acute spinal animals to electrical
stimulation of pelvic nerve afferents suggests that both propriospinal and
supraspinal circuits are involved in the intersegmental transmission of
input from bladder afferents to SPNs.
