The levels of FSH, testosterone, estradiol, and inhibin B were measured in each monkey.
Comparing the irradiated monkeys to the control monkeys, the average levels of FSH were significantly higher (6.1 ± 1.2 vs. 2.1 ± 0.1 ng/ml; P = 0.002) and of inhibin B significantly lower (691 ± 72 vs. 1227 ± 165 IU/ml; P = 0.02). Levels of testosterone as well as of estradiol were not significantly different (5.3 ± 0.8 vs. 7.6 ± 1.3 nmol/L and 16.5 ± 1.5 vs. 29.2 ± 6.7 pmol/L, respectively).
In the irradiated monkeys, FSH levels showed a significant negative relationship with testicular weight (P = 0.0025) and RI (P = 2.2 X 10 5) (Fig. 6, A and B). Highly significant positive correlations were found between the in-hibin B level and both testicular weight (P = 8.3 X 10_6) and RI (P = 7.4 X 10 5) (Fig. 6, C and D).
Of all monkeys and testes studied, only those presented in Table 1 showed enough recovery of the germinal epithelium to provide sufficient numbers of spermatocytes to be analyzed. The results of this multivalent analysis of spermatocytes at the diakinesis-metaphase I stage of meiosis are summarized in Table 1. Very few translocation configurations were present, and no induction by irradiation took place.
FIG. 6. The relationship between FSH or inhibin B levels and testicular weights or RI in adult rhesus monkeys irradiated before puberty (n = 29). A) FSH versus testicular weight (P = 0.0025). B) FSH versus RI (P = 2.2 X 10~5). C) Inhibin B versus testicular weight (P = 8.3 X 10~6). D) Inhibin B versus RI (P = 7.4 X 10~5).