Neural Pathway Innervating Epididymis of Rats by Pseudorabies virus (PRV-Ba-Gal) and WGA-HRP

Lee, Chang Hyun; Ko, Byoung Moon; Lee, Bong Hee; Chung, Ok Bong

Abstract

This experimental studies was to investigate the location of PNS and CNS labeled neurons following injection of 2% WGA-HRP and pseudorabies virus (PRV), beta-galactosidase inserted Bartha strain, into the epididymis of rats. After survival times 4~5 days following injection of 2% WGA-HRP and PRV-Ba-Gal, the rats were perfused, and their brain, spinal cord, sympathetic ganglia and spinal ganglia were frozen sectioned (30 mm). These sections were stained by HRP histochemical and beta-galactosidase histochemical staining methods, and observed with light microscope. The results were as follows : 1. The WGA-HRP labeled sympathetic ganglia projecting to the epididymis were observed in pelvic ganglion and L1-6 lumbar sympathetic ganglia. 2. The WGA-HRP labeled spinal ganglia projecting to the epididymis were observed in L1-6 spinal ganglia. 3. The beta-galactosidase labeled neurons projecting to the epididymis were observed in lamina VII of cervical segments. In thoracic segments, beta-galactosidase labeled neurons were observed in dorsomedial part of lamina I, II and III. Dense labeled neurons were observed in intermediolateral n. and dorsal commissural n.. In lumbar segment, labeled neurons were observed in lamina III, IV, V, dorsal commisural n. and superficial dorsal horn. 4. In the medulla oblongata, beta-galactosidase labeled neurons projecting to the epididymis were observed in the trigeminal spinal n., A1 noradrenalin cells/C1 adrenalin cells/caudoventrolateral reticular n., rostroventrolateral reticular n., area postrema, n. tractus solitarius, raphe obscurus n., raphe pallidus n., raphe magnus n., parapyra-midal n., lateral reticular n. and lateral paragigantocellular reticular n.. 5. In the pons, labeled neurons were observed in Kolliker-Fuse n., locus coeruleus, subcoeruleus n. and A5 noradrenalin cells. 6. In midbrain, labeled neurons were observed in periaqueductal gray substance, retrorubral n., substantia nigra and dorsal raphe n.. 7. In the diencephalon, labeled neurons were observed in paraventricular hypothalamic n., lateral hypothalamic nucleus., medial preoptic n. and retrochiasmatic n.. These results suggest that WGA-HRP labeled neurons of the spinal cord projecting to the rat epididymis might be the first-order neurons related to the viscero-somatic sensory and sympathetic postganglionic neurons, and beta-galactosidase labeled neurons of the brain and spinal cord may be the second and third-order neurons response to the movement of vascular smooth muscle in epididymis. These beta-galactosidase labeled neurons may be central autonomic center related to the integration and modulation of reflex control linked to the sensory and motor system monitoring the internal environment. These observations provide evidence for previously unknown projections from epididymis to spinal cord and brain which may be play an important neuroanatomical basic evidence in the regulation of epididymal function.