[The magnocellular hypothalamus (the main and accessory nuclei): the evolutionary, molecular biological and morphofunctional aspects].

In the hypothalamus of high vertebrates apart major magnocellular nuclei, accessory nuclei have been described. The review is devoted to evolution of the accessory nuclei and to some questions of molecular biology and histophysiology of neuroendocrine neurones composed these nuclei. On the basis of literary and original data author put forward the speculation that the accessory nuclei (dorsolateral, circular, forniceal, and anterior commissural) are evolutionary stable. These "untraditional" formations have a peculiarities of cell compositions and projections to neurohaemal regions (posterior pituitary, external zone of median eminence). In rats accessory nuclei might play a compensatory role in the osmotic stress condition as well as during ageing. One from accessory nuclei (forniceal nucleus) is involved in the neurogenic stress realization, another one (dorsolateral nucleus) participates in the regulation of endocrine pancrease and erection. The idea about functional differences among magnocellular hypothalamic nuclei is discussed.