Effect of exogenously administered estrogens on luteinizing hormone release in a complete testicular feminization syndrome patient with very low testosterone levels, before and after gonadectomy.

The response of LH to exogenously administered estrogens was evaluated in a 63-year-old patient affected by complete testicular feminization syndrome (CTFS) with very low testosterone (T) levels, before and after gonadectomy. Prior to gonadectomy a durative fall in gonadotropin levels was observed after estrogen administration, without observing of an estrogenic positive feed-back (EPF) from LH. After gonadectomy, following an initial decrement in both gonadotropins, the characteristic. LH peak was seen, 48 h after E2B (Estradiol Benzoate) administration. This observation, together with the very low T levels that we found in this patient, prompted us to construe that absence of EPF in males is not due, as previously believed, to a direct inhibitory action of T or E2, deriving from T aromatization, on the hypothalamus, but by a still unknown gonadal factor. The hypothesis that this factor has a tubular origin is formulated and discussed.