title: Occurrence of colloid-containing follicles in the pars distalis of pituitary glands from aging guinea pigs.
abstract: Colloid-containing follicles in the pars distalis of pituitary glands from guinea pigs at various ages ranging from 5 days to 36 months were examined by the periodic acid-Schiff (PAS) reaction, immunohistochemistry, and electron microscopy. The follicles storing PAS-positive colloid were first detected in 6-month-old animals, in which only a few follicles were present and mean diameters of colloid deposits were small: 4.3 +/- 1.0 microns in males and 4.1 +/- 0.4 microns in females. Thereafter, the follicles gradually increased in number and size with age. The largest number of follicles was observed in the senile groups: 410.5 +/- 92.3 in males, 454.7 +/- 84.7 in females. Mean diameters of colloid masses in the senile groups were more than 2 times larger than those in 6-month-old animals: 10.0 +/- 0.1 microns in males, 9.7 +/- 0.1 microns in females. These findings suggest that the formation of colloid-containing follicles in the guinea-pig pars distalis is an aging phenomenon. The follicular lumina were mainly surrounded by thin cytoplasmic processes or cell bodies of folliculo-stellate cells immunoreactive for S-100 protein. The lining folliculo-stellate cells showed aggregations of intermediate-sized filaments, numerous lysosomes and colloid-like inclusions. Granulated cells in contact with colloid were occasionally encountered. Intracellular cavities storing colloid-like and fibrous materials were detected in the syncytial formation of GH cells.
authors.affiliation: Department of Anatomy, Fukuoka University School of Medicine, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kameda
mesh_terms: D000375:Aging / Q000378:metabolism / Q000473:pathology*; D000818:Animals; D003102:Colloids; D005260:Female; D006168:Guinea Pigs; D007150:Immunohistochemistry; D008297:Male; D008854:Microscopy, Electron; D010503:Periodic Acid-Schiff Reaction; D010902:Pituitary Gland / Q000166:cytology* / Q000378:metabolism; D010907:Pituitary Hormones / Q000378:metabolism; D009418:S100 Proteins / Q000378:metabolism
chemical_list: D003102:Colloids; D010907:Pituitary Hormones; D009418:S100 Proteins