Abstract: | Steroid test substance 547 and Norgestrel were used in a combination treatment of parts of the hypothalamo-adenohypophyseo-gonadal axis of boars. The quantifiable parameters of the morphokinetic effect thus produced (cell nucleus volumes of Nucleus praeopticus medialis hypothalami and its neurons as well as those of Leydig's cells testicle weight, length and diameter of tube, percentage of Leydig's cells, testicle weight, length and diameter of tube, percentage of Leydig's cells) did not differ significantly from the findings obtained from boars treated with Norgestrel only (cf. Dorst and co-workder, 1978). The same combination treatment, however, differed from exclusive Norgestrel treatment by causing the occurrence of socalled castration cells, which led to the assumption of an anti-androgenic effect of such combination treatment. |