[Role of serotonin receptors of the medial-basal hypothalamus in the mechanisms of negative feedback of the hypophyseal-testicular complex].

Administration of serotonin into the lateral ventricle of the brain of male rats, against the background of complete isolation of the medial-basal hypothalamus was accompanied by the block of the compensatory elevation of the blood testosterone level following unilateral castration. Experiments with local serotonin administration into the hypophysial region of the hypothalamus of hemicastrated rats indicated that the inhibitory effect produced by the excitation of the serotonin receptors of this region on the mechanism of the negative feedback of the hypophysis-testicular system was realized at the arcuate nuclei level.