Neurons in the rat brain and spinal cord labeled after pseudorabies virus injected into the external urethral sphincter

Abstract

Male Sprague-Dawley rats, with their pelvic and hypogastric nerves transected, were infected with pseudorabies virus (PRV) injected into the external urethral sphincter. Animals were sacrificed at 2, 2.5, 3, and 4 days postinfection. Spinal cord and brain tissue were sectioned and processed by immunohistochemical techniques with antisera against PRV and choline acetyl transferase (CAT). At 2 days postinfection, virus-labeled neurons were found in the ventrolateral divisions of Onuf's nucleus 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 neurons 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 preganglionic neurons. After 4 days, virus had spread to neurons in the paraventricular, preoptic, and even cortical regions. The distribution of these PRV-labeled brain neurons strongly resembled that obtained after the injection of PRV into the urinary bladder (Nadelhaft et al. [1992] 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 and the external urethral sphincter.

Projections from bed nuclei of the stria terminalis, magnocellular nucleus: Implications for cerebral hemisphere regulation of micturition, defecation, and penile erection

“…Transneuronally labeled neurons are observed in all brain regions just mentioned following pseudorabies virus injections into pelvic organs of the rat, including the urinary bladder (Nadelhaft and Vera, 1995), urethra (Vizzard et al, 1995), external urethral sphincter (Nadelhaft and Vera, 1996), ischiocavernosus and bulbospongiosus muscles (Marson and McKenna, 1996;Tang et al, 1999), penis (Marson et al, 1993), and colon (Valentino et al, 2000;Vizzard et al, 2000). In some of these analyses, transneuronally labeled neurons were reported in the vicinity of the BSTmg .…”

Transplantation of Neuronal and Glial Restricted Precursors into Contused Spinal Cord Improves Bladder and Motor Functions, Decreases Thermal Hypersensitivity, and Modifies Intraspinal Circuitry

“…Several sites in the brainstem project serotonergic axons into the lumbosacral spinal cord. These pathways, particularly those projecting to the DL, have been implicated in the central control of bladder and urethra and recovery of bladder-external urethral sphincter coordination in SCI rats (Ding et al, 1995;Vizzard et al, 1995;Nadelhaft and Vera, 1996;Marson, 1997;Pikov and Wrathall, 2001). 5-HT-positive fibers in the DL were more densely distributed in NRP/GRP compared with OP-controls but less than in unoperated controls rats.…”

Neural Control of the Lower Urinary Tract

“…Transneuronal PRV tracing methods have also identified many populations of neurons in the rat brain that are involved in the control of bladder (460,462,463,604), urethra (664), and the EUS (402,461,462), including the PMC (Barrington's nucleus), PAG, medullary raphe nuclei, which contain serotonergic neurons; the locus coeruleus (LC), which contains noradrenergic neurons, and the A5 noradrenergic cell group (Fig. 11).…”