Effects of castration on the expression of brain-derived neurotrophic factor (BDNF) in the vas deferens and male accessory genital glands of the rat

Abstract

Brain-derived neurotrophic factor (BDNF) is a growth factor belonging to the family of neurotrophins. Although neurotrophins in the male genital organs have been well documented, their role in the biology of these organs is far from clear. In particular, little is known about the influence of sex hormones on neurotrophin expression. In the present study, using immunohistochemistry and enzyme-linked immunosorbent assay (ELISA), we investigated the distribution and tissue concentration of BDNF in the vas deferens and accessory male genital glands in normal and castrated rats. The expression of BDNF mRNA was also investigated. In normal rats, BDNF immunoreactivity was localized in the musculature of the vas deferens and vesicular gland and in the fibromuscular stromal cells of the prostate. In the ventral prostatic lobes, BDNF immunoreactivity was localized in basal, secretory and neuroendocrine epithelial cells. Innervating ganglia and nerves were immunoreactive in all the examined tracts. After castration, BDNF immunoreactivity increased in the musculature of the vesicular gland and in the fibromuscular stromal cells of both dorsal and ventral prostatic lobes. BDNF immunoreactivity also increased in the nerves. ELISA and reverse transcription/real-time polymerase chain reaction confirmed the findings of the immunohistochemical study. In the accessory glands, castration induced an increase of both BDNF tissue concentration and mRNA expression. These results suggest that BDNF is expressed in the internal male genital organs of the rat and that its expression is downregulated by androgen hormones. We hypothesize that the observed BDNF increases are related to the castration-induced regression of the sympathetic nerves.

Effects of castration on the immunoreactivity to NGF, BDNF and their receptors in the pelvic ganglia of the male rat

“…The data regarding p75 NTR -immunoreactivity appear in contrast with previous findings reporting an increase of p75 NTR -immunoreactivity in the nerves of the internal genital organs of castrated rats (Mirabella et al, 2007). The reasons of this discrepancy remain to be clarified.…”

“…This result suggests that androgens positively modulate BDNF synthesis and/or its receptor affinity in the pelvic neurons.This seems to be in contrast with previous findings reporting an increase of BDNF expression in the accessory male genital glands (i.e. one of the targets of the pelvic innervation) of the rat after castration (Mirabella et al, 2006;Mirabella et al, 2007). Thus, a difference can be hypothesized for androgen hormones in influencing their target tissues.…”

“…Recent studies suggest that the expression of BDNF, TrkB and p75 NTR in the vas deferens and accessory male genital glands of the rat is influenced by androgen hormones (Mirabella et al 2006;Mirabella et al, 2007).…”

Innervation and Immunohistochemical Characteristics of Epididymis in Alpaca Camelid (Vicugna Pacos)

“…The autonomic innervation plays a key role in regulation of male genital functions. Anatomical, pharmacological and physiological data (Hib, 1976;Laitinen and Talo, 1981;Pholpramool and Triphon, 1984;Mirabella et al, 2006Mirabella et al, , 2008Squillacioti et al, 2008Squillacioti et al, , 2009 suggest that the role of adrenergic and cholinergic inner- (Farrel and Lyman, 1937;Sjostrand, 1965;Mirabella et al, 2007) and blood flow (Baumgarten and Holstein, 1968;Kuwahara and Frick, 1974;Damber et al, 1982;Billups et al, 1990;Santamaria et al, 1995). Epithelial exo/endocytic events and ionic exchange between cellular and luminal compartments are other processes that are influenced by autonomic innervations (Mayerhofer et al, 1992;Chan et al, 1994;Kempinas et al, 1995;Lamano-Carvalho et al, 1996;Zhu et al, 1998).…”

Effects of castration on the expression of the NGF and TrkA in the vas deferens and accessory male genital glands of the rat

“…Recently, in the vas deferens and accessory male genital glands of the rat, the expression of the BDNF and its receptors (TrkB and p75NTR) has been reported to be regulated by androgen hormones (Mirabella et al, 2006;Mirabella et al, 2008). In castrated rats, moreover, BDNF has been hypothesized to regulate, via interacting p75NTR, the castration-induced regression of the sympathetic innervation (Mirabella et al, 2006).…”