Nucleolus-like bodies in the pineal gland of the Djungarian hamster (Phodopus sungorus).

Light- and electron-microscopic observations on the pineal gland of Phodopus sungorus revealed intracytoplasmic inclusions resembling nucleolus-like bodies similar to those found in other regions of the central nervous system. Bernhard's EDTA method was used to confirm that these inclusions were nucleolus-like bodies. These structures were rarely found in pinealocytes of sexually active long-day animals, whereas large numbers of them were observed in pinealocytes of sexually quiescent short-day animals. Nucleolus-like bodies may therefore be involved in pineal secretion.