MORPHOMETRIC AND STEREOLOGICAL STUDY OF THE GLANDULAR EPITHELIUM THE SEMINAL-VESICLE OF CASTRATED GUINEA-PIGS TREATED WITH 17-BETA-ESTRADIOL BENZOATE

Morphometric and stereological data are presented showing that the ave rage thickness of the glandular epithelium (including secretory and ba sal cells together with intercellular spaces) of the seminal vesicle o f the guinea pig increased significantly after oestradiol administrati on when compared with castrated controls. The increase in thickness wa s accompanied by a significant increase in the volume density of inter cellular spaces. There were significant decreases in volume, surface a nd numerical densities of the secretory cell nuclei with respect to th e glandular epithelium. The increase in the volume and surface densiti es of the secretory cell nuclei with respect to the average secretory cell was due to the significant increase in the average volume of the secretory cell. The increase in the mean volume of secretory cells was the result of a significant increase in the average cytoplasmic volum e. In comparison with castrated controls, the structural data of cytop lasmic organelles also showed significant increases in total volume an d surface area of granular endoplasmic reticulum per average secretory cell following oestradiol administration. This was accompanied by a s ignificant increase in the total volume of Golgi cisternae per cell. T he increase in the cytoplasmic volume of secretory cells after oestrad iol treatment may be the result of an increase in number of organelles responsible for protein synthesis. The present study has provided qua ntitative evidence that the secretory function of the seminal vesicle of castrated guinea pigs may have been stimulated after oestradiol adm inistration, which cannot be easily detected in a qualitative manner.