Studies on the lipofuscin pigment in the brain of Rana temporaria L. in the annual cycle. II. Tuber cinereum.

Sexually mature Rana temporaria L. frogs were captured in their natural habitat in seven stages of the the annual cycle. The volume of the nuclei of neurocytes of the pars dorsalis of the tuber cinereum containing lipofuscin pigment underwent significant changes in the course of the year. In both sexes the nuclear volume of the neurocytes was greatest in the terminal stage of winter sleep (1st decade of March), and smallest at the beginning of active life (3rd decade of May). The accumulation of lipofiscin pigment varied parallel to the changes in mean volume of the neurocyte nuclei of the pars dorsalis of the tuber cinereum.