Circatrigintan rhythm, melatonin hypothesis of depressive disorders and ultrastructural changes of pinealocytes in experiment

For testing the circatrigintan rhythm of the activity of the pineal gland, that has an effect on the manifestation of depressive disorders, with methods of electron microscopy in intact and those subjected to 48 - hour illumination by the bright light rats, kept under conditions of the invariable daily photophase, the dynamic estimation of the ultrastructural markers of the secretory activity of pinealocytes - of synaptic ribbons and osmiophilic bodies has been carried out. The length of the active region of the contact of synaptic ribbons and the elongation of the osmiophilic bodies of pinealocytes both during the phase of the normalization of the functional state of pineal gland in the hyper-illuminated rats and without a change in the daily regime of illumination, manifested periodicity, close to one month. Syn chronously with a change in the synaptic ribbons and osmiophilic bodies the components of cytoskeleton, mitochondria, rough endoplasmic reticulum of pinealocytes were reconstructed. According to criteria of ultrastructural analysis the conclusion about the universal nature of the circatrigintan rhythm of changes of the functional state of pineal gland of rats in the normal state and under stress is made.