The protein concentration in the final (testis and liver) preparations was determined in duplicate by the bicinchon-inic acid method (BCA protein assay reagent; Pierce, Rockford, IL), with BSA as standard. The level of plasma GH was determined using a homologous RIA developed in our laboratory . The sensitivity of the assay (££>90) is 0.1 ng/ml for 50 |xl of assayed plasma, and the ED5 is 0.6 ng/ml. buy ortho tri-cyclen online
For each spermatogenetic stage, affinity constants (Ka) and binding capacities (Bmax) were calculated according to the method of Scatchard . Scatchard plot analyses were performed with free hormone values corrected for MBA. Scatchard plots were compared using covariance analysis. The statistical difference between groups was examined by one-way analysis of variance followed by multiple range test. Differences were considered significant when p < 0.05. Linear regression analysis was used to determine the relations between the different variables. All results are expressed as the mean ± SEM.