RESUMEN
OBJECTIVE: To evaluate whether fluorescent tracers can consistently label the neurovascular bundles (NVBs) and major pelvic ganglion (MPG) after an intracavernosal penile injection, as the reported incidence of erectile dysfunction (ED) in men after radical prostatectomy (RP) is 55-65% and thus preservation of erectile function, sparing one or both of the NVBs remains one of the most vital factors. MATERIALS AND METHODS: Male Sprague-Dawley rats (3 months old) received penile injections (20 microL; seven rats/group) of either deionized water (DW), Fluoro-Gold (FG), Fast-Blue (FB), Fluoro-Ruby (FR) or green fluorescent pseudorabies virus (GF-PRv). The rats were killed at 2, 3 and 14 days after injection and the NVBs and MPG were harvested and placed directly under fluorescence light. Image analysis was done by computer, coupled to a microscope equipped with a digital camera. Each NVB and MPG were analysed for its staining pattern and consistency. RESULTS: When compared with the FB, FR and GF-PRv rats, the FG-injected rats had better staining of the NVB at 2, 3 and 14 days after injection. Under x200, FG highlighted the axons of the cavernous nerve (CN) and cell bodies (MPG). This indicates that FG injection into the penis induced the strongest CN labelling (positive staining) at 2 and 3 days after injection as compared with FB-, FR- and GF-PRv-injected rats. CONCLUSION: FG injection into the penis has consistent retrograde staining of the NVBs and MPG after 3 days. Therefore, we predict that FG could potentially be used to improve the identification of the NVB in other models. However, further studies need to be carried out before these tracers can be used in humans.
Asunto(s)
Microscopía Fluorescente/normas , Erección Peniana/fisiología , Pene/inervación , Vías Aferentes/fisiología , Animales , Vías Eferentes/fisiología , Disfunción Eréctil/prevención & control , Inyecciones , Masculino , Pene/fisiopatología , Prostatectomía/efectos adversos , Ratas , Ratas Sprague-DawleyRESUMEN
Fluorogold or green fluorescent pseudorabies virus labeled postganglionic neurons in the pelvic ganglion that innervate the prostate gland. Small cholinergic neurons were demonstrated by immunohistochemistry (IHC) with antiserum against vesicular acetylcholine transferase (VAChT). Large, mainly adrenergic neurons, were surrounded by preganglionic cholinergic boutons. In the prostate, M3 type muscarinic receptors were found in the outer muscle layer surrounding the prostatic acini. The antiserum against VAChT marked the inner epithelial layer. Antisera against the vesicular monoamine transporters VMAT1 and VMAT2 demonstrated staining of the inner secretory layer and adrenergic fibers in the outer muscle layer, respectively, of the prostatic acini. These results provide new evidence for the presence of neural elements that have a cholinergic influence over the rat prostate gland.
Asunto(s)
Axones/química , Fibras Colinérgicas/química , Plexo Hipogástrico/química , Neuronas/química , Próstata/química , Animales , Axones/fisiología , Fibras Colinérgicas/fisiología , Ganglios Parasimpáticos/química , Ganglios Parasimpáticos/fisiología , Plexo Hipogástrico/fisiología , Masculino , Neuronas/fisiología , Próstata/inervación , Próstata/fisiología , Ratas , Ratas Sprague-DawleyRESUMEN
BACKGROUND: This work examines the central nervous system distribution of virus-labeled neurons from the rat urinary bladder and the prostate simultaneously within the same tissue sections. Two immunohistochemically distinct pseudorabies virus strains were simultaneously injected into male Sprague Dawley rats (approximately 280 gm). One virus was injected into the bladder and the other into the prostate. After incubation intervals of 2.25, 2.5, 2.75, 3 and 4 days, sections from the spinal cord and brain were processed immunohistochemically to detect cells, within a single section, which were labeled separately by each virus or were labeled by both viruses. RESULTS: Each strain of virus labeled a separate population of neurons and some neurons were labeled by both strains. The majority of neurons labeled by virus from the urinary bladder were found in the L6-S1 spinal cord segments within the dorsal gray commissure, the intermediolateral area and the superficial dorsal horn. Neurons labeled by virus from the prostate were mainly found in the L1-L2 spinal cord segments in the dorsal gray commissure and the intermediolateral areas. Double-labeled interneurons in L1-L2 were mainly located in the intermediolateral area. In L6-S1 they were divided between the dorsal gray commissure and the intermediolateral area. CONCLUSIONS: Spinal neurons innervating the bladder are clearly separate and different from those innervating the prostate. This difference also persists in the brain. In disagreement with previous reports, no direct anatomical evidence of parasympathetic innervation of the prostate was observed.
Asunto(s)
Sistema Nervioso Central/citología , Herpesvirus Suido 1 , Neuronas/citología , Próstata/inervación , Vejiga Urinaria/inervación , Animales , Encéfalo/citología , Encéfalo/virología , Sistema Nervioso Central/virología , Herpesvirus Suido 1/fisiología , Inmunohistoquímica , Masculino , Neuronas/virología , Próstata/citología , Próstata/virología , Ratas , Ratas Sprague-Dawley , Médula Espinal/citología , Médula Espinal/virología , Sistema Nervioso Simpático/citología , Sistema Nervioso Simpático/virología , Vejiga Urinaria/citología , Vejiga Urinaria/virologíaRESUMEN
BACKGROUND: We previously showed that systemic administration of the atypical neuroleptic clozapine in the rat altered a number of urodynamic variables and inhibited the external urethral sphincter. Since clozapine acts at several receptor types both at the periphery and the central nervous system, the site of action remained uncertain. Therefore, the purpose of this study was to determine the effects of central administration of clozapine on the bladder and the external urethral sphincter during cystometry and to examine differences in spinal versus supraspinal administration. We extended our observations by delivering clozapine centrally in anesthetized rats instrumented with either an intrathecal (L6-S1 spinal segment) or an intracerebroventricular (lateral ventricle) catheter. RESULTS: Clozapine decreased micturition volume and increased residual volume possibly by acting at a supraspinal site. Expulsion time and amplitude of the high frequency oscillations were reduced by clozapine possibly by acting at a spinal site. Bladder capacity was increased after central clozapine but probably due to a peripheral effect. Clozapine acting at spinal and supraspinal sites increased pressure threshold. Contraction time and peak pressure were not affected by clozapine. The EMG from the external urethral sphincter was also reduced following clozapine centrally and suggests a spinal and a supraspinal site of action. CONCLUSIONS: The results from the present study suggest that spinal and supraspinal central sites mediate clozapine's action in inhibiting expulsion parameters and the external urethral sphincter of the rat. Therefore, the reduction in the voiding efficiency observed after clozapine appears to be mediated by spinal and supraspinal sites.