Aims of the Study:
Disease in the pelvic area often involves different organs, i.e., urinary and fecal incontinence, pain and chronic "abacterial" inflammation of bladder and prostate. It is known that the Central Nervous System (CNS) plays a major role in modulating lower urinary tract function. Disturbance of peripheral and central reflex pathways are responsible for severe dysfunction and development of chronic disease in the pelvic area. Centers within the brain and brain stem modulating pelvic organ function are known. However, there are no data about differences in the number of neurons projecting to different pelvic organs. There may be differences in the number of pontine neurons projecting to the prostate and the bladder.

Methods:
Adult male Sprague?Dawley rats were used for retrograde transneuronal mapping of the brain and brain stem. A pseudorabies virus (PRV) tracer (5ml, 1x108pfu/ml) was injected into the bladder trigone of 32 animals and into the prostate gland of 44 animals. After 72, 96 and 120 houres post injection the animals were sacrifized and the whole CNS harvested. After immunohistochemistry a comparing analysis regarding neuron density in different areas of the brain and brain stem were carried out.

Results:
There are statistically significant differences (p < 0.05) in the neuron density of central areas involved in innervation of the bladder trigone and prostate. The density of PRV-positive neurons after injection into bladder and prostate was found to be different within the following areas: periaquaductal gray, hypothalamus, pontine micturition center, locus coeruleus, A5 noradrenergic area and lateral reticular formation. No difference was found in the medial preoptic region, nucleus raphe and gigantocellularis.

Conclusions:
There is a difference regarding the neuron number within one supraspinal area innervating different pelvic organs. Different organs receive input from same centers but there is a difference in the number of efferent cells connected to the pelvic organ.