GnRH agonist induces apoptosis in seminiferous tubules of immature rats: Direct gonadal action

To investigate direct gonadal effect of buserelin as an agonist of gonadotrophin
releasing hormone, the incidence of apoptotic cell death was measured. Thirty
25-day-old immature Wistar male rats were divided into two groups: treated
and control rats. Treated rats were given 1.25 mg buserelin acetate/g body weight
control rats received vehicle subcutaneously for 5 days. Formalin-fixed paraffin
embedded testicles were then investigated for the morphology of seminiferous
tubules and occurrence of apoptosis using haematoxylin-eosin staining and terminal
deoxynucleotidyl transferase-mediated dUTP nick-end labelling respectively.
Immaturity of rats was proved by the morphological characteristics of
testis. In contrast to the control rats, significant increase of apoptotic cell death
was found in buserelin-treated rats. Apart from the well-known pituitary-testicular
function of buserelin as an agonist of gonadotrophin releasing hormone, our
findings suggest that it induces apoptotic cell death via direct gonadal action.