Showing papers on "Pinealocyte published in 1971"

Development of the innervation in the human pineal organ. Light and electron microscopic investigations.

Abstract: This investigation is concerned with pineal organs of human embryos 60 to 150 days old. At every stage central nerve fibres enter the pineal organ by way of the habenular commissure, but are restricted to the pineal's proximal part. On about the 60th day of the development the sympathetic nervus conarii grows into the distal pole of the pineal organ from a dorso-caudal direction and plays the predominant part in the innervation of the pineal organ. After penetrating, it soon branches out and forms a network in the pineal tissue. Much later, not until the 5th embryonic month, sympathetic nerves appear accompanying the supplying vessels in the perivascular spaces. After a short time these nerves pierce the outer limiting basement membrane and penetrate the parenchyma. Towards the end of the 5th embryonic month the axons of the sympathetic nerves form varicosities containing clear and dense core vesicles. At this point large amounts of laminated granules appear primarily in cell processes, probably of pinealocytes. Isolated granules also occur in the varicosities of axons. The granules encountered here are most likely secretory granules.

Annulate lamellae in hamster pineal gland

Abstract: Pineal glands from young adult hamsters ( Mesocricetus auratus Water-house) kept on a 14–10 light-dark photoperiod contain annulate lamellae. These annulate lamellae are apparently limited to the light pinealocytes. They are found in close proximity to nuclei, the Golgi apparatus, and agranular endoplasmic reticulum. There is also an interesting association or microtubules with the annulate lamellae. It seems reasonable that the presence of annulate lainellae in the pinealocytes may have some correlation with the physiological function or functions of these cells.

Organization and histology of the pineal region in the hyrax (Procavia capensis).

Abstract: The pineal region of four adult male Procavia capensis from South Africa was studied in serial sections of median portions of entire brains. A consistent and unique pineal morphology was found in all specimens, in contrast with previous reports based on specimens of Procavia from diverse and distant populations or species. A principal pineal tissue mass bounds the pineal recess anterodorsally and makes contact with the subcommissural organ at the apex of the recess. A dorsal or accessory pineal tissue mass occurring on the opposite (anterior or dorsal) side of the habenular commissure forms part of the basal wall of the dorsal sac. Both pineal parts are penetrated throughout by nerve fibers, of which at least the great majority belong to the habenular commissure system. Tissue zonation, rich and distinctive vascularization, abundant pinealocytes in lobules, and parenchymal follicles are also characteristic. The dorsal sac and pineal recess are unusually large in this species. Additional features of the pineal body, dorsal sac and subcommissural organ are described.