ACCEPTED LECTURE

Abstract:
Cancer is one of the diseases with the highest incidence nowadays. In men, prostate cancer is the most frequent and its incidence increases with age. The used treatment is focused on blocking the effect of androgens, but this is not completely successful because the cases of severe diseases or deaths are still increasing. The underlying reason is still unknown, but an answer could include a possible role of the autonomic nervous system (ANS) that shows a complex innervation to the prostate. This gland is supplied by postganglionic fibers that arrive from the major pelvic ganglion (MPG) that, in turn, is supplied by both the hypogastric nerve (HgN) and the viscerocutaneous branch of the pelvic nerve (PvN). The exact function of this innervation to the prostate is not yet full understood, but it includes a complex circuit of central neurons located at different nuclei of the brain, and some of them are also involved in the control of sexual behavior. MPG is a mixed ganglion because it receives sympathetic (HgN) and parasympathetic (PvN) fibers, and it is proposed that the sympathetic innervation controls prostate growth, while the adrenergic innervation is involved with the control of secretion. On the other hand, it has been reported that alteration in prostate innervation produces inflammatory or proliferative lesions, but its effects on testosterone release are still contradictory. Thus, the purpose of this work was to analyze the effect of sexual behavior and preganglionic axotomy on systemic testosterone levels, gland weight and the expression of androgen, cholinergic and adrenergic receptors. To do this, denervated prostates from intact and sexually experts rats were used. Testosterone levels were analyzed by ELISA and the expression of the receptors was analyzed by Western blot (proteins) and by RT-PCR (messenger). Results indicated that a) Sexual behavior was not affected by axotomy; b) Blood testoterone levels increased due to sexual behavior but is not observed after axotomy; c) The weight of ventral prostate increased with sexual behavior but was not affected by axotomy; d) AR messenger level increased with sexual behavior but were not altered by axotomy; e) The messenger for adrenergic and cholinergic receptors decreased after denervation of both nerves, while for muscarinic receptors increased; f) Only AR protein decreased after axotomy of both nerves. Based on these results, it is concluded that the three receptors have different regulations, and the androgen receptor is the only one that requires the involvement of both nerves to reduce its levels; this could be an important factor to initiate the lesions reported in the prostate.