[Accessory groups of nonapeptidergic cells in the diencephalon of intact and hypophysectomized rats]. / Dopolnitel'nye gruppy nonapeptidergicheskikh kletok promezhutochnogo mozga u intaktnykh i gipofizéktomirovannykh krys.

Accessory groups (AG) of oxytocin (OT)--and vasopressin (VP)--ergic cells (circular, perifornical, ventro- and dorsolateral groups and periventricularly localized nonapeptidergic cells) were studied morphometrically in intact and hypophysectomized rats. Additionally, the AG of medulla stria thalamus was demonstrated and investigated. The total number of nonapeptidergic cells in the AG is about 600 cells. The AG consist of OT-ergic cells predominantly (58%) except the perifornical group (68%) VP-ergic cells) and ventrolateral group (equal propotion). 7 days after hypophysectomy the size of perikaryon, nucleus and nucleolus of the cells in AG decreased, though, in contrast to the supraoptic and paraventricular hypothalamic centres, no degeneration of cell occured. That is why it is possible to suggest, that axons of the AG cells do not project to the posterior pituitary. The absence of hypertrophy of the AG cells in compensatory function of degenerating cells in the supraoptic and paraventricular nuclei indicates a functional diversity of these nonapeptidergic cells.