Development and histology of the pineal gland in humans
Kitapta bölümler · 2011
Yazarlar: Yiğit UYANIKGİL, Mehmet Turgut, Meral Baka
The Pineal Gland and Melatonin: Recent Advances in Development, Imaging, Disease and Treatment, Nova Science Publishers, Inc., Uluslararası, 2011, ss 55-69,
Özet
The pineal gland is a photosensitive organ, an important timekeeper and regulator of the day/night cycle, called circadian rhythm. In humans, the pineal organ is located at the posterior wall of the third ventricle near to the center of the brain. It develops from neuroectoderm of the posterior portion of the roof of the diencephalon and remains attached to the brain by a short stalk. The pineal gland consists of several types of cells, principally pinealocytes and astrocytes. Histologically, pinealocytes have a slightly basophilic cytoplasm with large irregular or lobate nuclei and sharply defined nucleoli. When impregnated with silver salts, the pinealocytes appear to have long and tortuous branches reaching out to vascular connective tissue septa, where they end as flattened dilatations. These cells produce melatonin and some ill-defined pineal peptides. This chapter summarizes the embryonic development and histogenesis of the pineal gland, and defines the histological features of pinealocytes and astrocyte-like cells in the pineal gland, with particular reference to light and electron microscopical as well as immunohistochemical characteristics. © 2012 Nova Science Publishers, Inc. All rights reserved.