[Amygdaloid complex in the gonadectomized rat, reaction of the neurons of the cortico-medial region].

A karyometric investigation of 22 zones of the cortico-medial group of the rat amygdaloid complex (AC) nuclei has been undertaken in order to reveal the area responding to gonadectomy. Mature rats are killed one month after castration. Their brains are fixed in 10% neutral formalin, paraffin sections are stained with hematoxylin--eosin. In each animal (20 animals in all) 200 cellular nuclei are measured in every zone. Projections of the nuclei are drawn. Their volume is estimated according to the formula of the ellipsoid volume rotation. All the main parameters characterizing distribution of the nuclear volume log in the zones studied are calculated; significance of differences are carried out according to the criteria of t Student and X2. As demonstrates the analysis of the data obtained, in male rats the following area respond to gonadectomy: neurons of the anterior amygdaloid area of the dep zone of the anterior cortical nucleus, of the central nucleus, of the posterior intercalated masses, of the dorsomedial nucleus, of the posterior medial nucleus and of the medial part in the posterior cortical nucleus. In female rats anterior parts of the central nucleus, medial and basomedial nuclei at the level of the main trunk in the terminal strip, the dorsomedial nucleus, the periventricular zones, the posterior medial nucleus and the medial part of the posterior cortical nucleus become sensitive to the experimentally produced deficit of the sex hormones. The results obtained demonstrate that together with certain similarity, there are some sex differences in the topography of the AC zones responding to gonadectomy.