I. Nadelhaft et Pl. Vera, NEURONS IN THE RAT-BRAIN AND SPINAL-CORD LABELED AFTER PSEUDORABIES VIRUS INJECTED INTO THE EXTERNAL URETHRAL SPHINCTER, Journal of comparative neurology, 375(3), 1996, pp. 502-517
Male Sprague-Dawley rats, with their pelvic and hypogastric nerves tra
nsected, were infected with pseudorabies virus (PRV) injected into the
external urethral sphincter. Animals were sacrificed at 2, 2.5, 3, an
d 4 days postinfection. Spinal cord and brain tissue were sectioned an
d processed by immunohistochemical techniques pith antisera against PR
V and choline acetyl transferase (CAT). At 2 days postinfection, virus
-labeled neurons were found in the ventrolateral divisions of Onuf's n
ucleus and in the dorsal gray commissure (DGC). At progressively later
incubation times, labeled neurons were found in the intermediolateral
regions, the superficial layer of the dorsal horn, and the brainstem,
in particular, the pontine micturition center. PRV/CAT-positive neuro
ns were only found in Onuf's nucleus. Preganglionic neurons in the L6-
S1 intermediolateral regions were CAT positive but PRV negative, thus
suggesting that they are interneurons, not sacral parasympathetic preg
anglionic neurons. After 4 days, virus had spread to neurons in the pa
raventricular, preoptic, and even cortical regions. The distribution o
f these PRV-labeled brain neurons strongly resembled that obtained aft
er the injection of PRV into the urinary bladder (Nadelhaft et al. [19
92] Neurosci. Lett. 143:271-274). In both cases, neurons were labeled
in the DGC in the spinal cord. The data therefore suggest that neurons
in the DGC may be involved in the integrated control of the bladder a
nd the external urethral sphincter. (C) 1996 Wiley-Liss, Inc.