title: Fine structural alterations in the aging rat pineal gland.
abstract: The pineal glands of 1 mo to 28 mo old male and female rats were examined by electron microscopy. With increasing age the following observations were made: (1) the capsule thickness increases; (2) there is an increase in collagen infiltration; (3) increased amounts of granular deposits are seen between cells; (4) there is a greater variability in the number of light pinealocytes; (5) pinealocytes with nuclear invaginations and pinealocytes with nuclear inclusions increase in number; (6) more cytoplasmic dense bodies are seen in pinealocytes and gliocytes; (7) the maximum diameter of pinealocyte lipid droplets tends to increase; (8) no definite change is observed in granular endoplasmic reticulum; (9) occasional cells are found to contain reticulated mitochondria, and a few cell processes have an appearance similar to neuroaxonal dystrophy. Besides illustrating age-rated changes, the present study proves the existence of pinealocyte nuclear inclusions, suggests the possibility of pineal concretions in the rat, and morphometrically or semi-morphometrically analyzes several structural features not previously quantified.
mesh_terms: D000375:Aging; D000818:Animals; D002467:Cell Nucleus / Q000648:ultrastructure; D003094:Collagen / Q000378:metabolism; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D005260:Female; D002479:Inclusion Bodies / Q000648:ultrastructure; D050356:Lipid Metabolism; D008062:Lipofuscin / Q000378:metabolism; D008297:Male; D008928:Mitochondria / Q000648:ultrastructure; D009457:Neuroglia / Q000648:ultrastructure; D009474:Neurons / Q000648:ultrastructure; D010870:Pineal Gland / Q000033:anatomy & histology*; D051381:Rats
chemical_list: D008062:Lipofuscin; D003094:Collagen