MORPHOLOGICAL-STUDIES ON PREPUTIAL GLAND OF MICE .1. LIGHT AND TRANSMISSION ELECTRON-MICROSCOPIC OBSERVATIONS OF PREPUTIAL GLAND IN MALE-MICE

Male BALB/c mice isolated after weaning were housed two mice per cage at the age of 10 weeks. After 1 week, each pair of mice was observed f or social dominance, and compared with control mice kept in isolation. The preputial gland in the socially dominant animal was histologicall y examined. The preputial gland consisted of a congregation of branche d simple tubuloacinar gland and typical holocrine secretion on morphol ogical examination. Acinar cells in the dominant animals were large, m ultiplicative and hypertrophic compared with those of controls and sub ordinates. Dominant animals required copious secretion for attainment and maintenance of a,dominant social position. Acinar cells of subordi nates were very small, flattened and atrophied because fatty secretion particles filled the luminal duct. These accumulated secretion partic les pressed the acinar cells and caused degeneration. Not only luminal acinar cells but also central acinar cells and some basal. acinar cel ls were degenerated. Electron micrographs showed that basal acinar cel ls in dominant animals contained many mitochondria, agranular endoplas mic reticulum and free ribosomes in the cytoplasm, whereas those of su bordinates contained myelin bodies and lipid droplets. Therefore, it i s suggested that the synthesis of secretion particles in acinar cells of subordinates hardly occurred.