Australian Regenerative Medicine Institute

Effects of Photoperiod and Age: MATERIALS AND METHODS(3)

Hormone Assays

Concentrations of LH, T, and T4 were determined by validated RIA. The LH RIA has been described by Bacon and Long. The LH used for iodination and standard was of chicken origin (USDA-cLH-K-3), and the primary antiserum was raised in rabbits using this LH as antigen. The sample volume was 100 ^l for this assay. The intra-and interassay coefficients of variation (CV) were 6.0% and 8.4%, respectively. Extraction and RIA for T were as described by Bacon et al.. Aliquots of 20 ^l (mature toms) or 50 ^l (immature toms) of plasma were used. The intra-and interassay CV were 8.1% and 12.0%, respectively. The T4 RIA was conducted using an ICN T4 RIA kit (ICN Pharmaceuticals, Inc., Costa Mesa, CA). The intra- and interassay CV were 3.6% and 6.4%, respectively. buy cipro

Data Analysis

For trials 1 and 2, data were analyzed with repeated measures ANOVA with age and treatment within age as factors. Single degree of freedom comparisons of treatments at each age were used to determine age-specific treatment effects. For trial 3, the PULSAR algorithm was used to calculate the overall mean level, baseline level, pulse number/9 h, and pulse amplitude. The G values for PULSAR analysis for Lh and T were G = 3.80, G = 2.60, G = 1.90, G = 1.50, G = 1.20. The assay SD calculated and used for LH and T PULSAR analysis were 5.67x + 1.40/100 and 7.15x + 2.10/100, respectively, where x is the concentration of LH and T in the individual sample. Testes weight, and overall mean concentration, baseline concentration, pulse amplitude concentration, and pulse number/9 h of the hormones were analyzed by ANOVA with age and treatment within age as factors. Statistical significance among means was evaluated with Duncan’s multiple range test. Coincidence of LH and T pulses was determined manually based on results from PULSAR analysis.

Category: Semen Production

Tags: Luteinizing Hormone, Male, Semen Production, Testosterone