Cytometric study of the female Syrian hamster gallbladder epithelium following sex steroid administration

This report is a cytometric study of the female Syrian hamster gallbladder epithelium following 1-, 2-, and 3-month administration of female sex steroids. Nulliparous, multiparous, young, old and pregnant hamsters were used in this study. A 1 month treatment with estrogen alone significantly increases the nuclear volume of the gallbladder epithelial cells, while E + P treatment significantly affects the nuclear volume only after a 2 month treatment. On the other hand, E + P and P treatments significantly increase the cell volumes as compared to the E-treated groups, this effect is most striking following the 1 month period. Prolonged sex steroid treatment (2 and 3 month) does not appear to influence the gallbladder epithelial cell and nuclear volumes as dramatically as that observed following the 1 month treatment. The nulliparous, progesterone-treated hamsters appear to have a greater cytoplasmic volume than the multiparous group and this is substantiated by the bulging apices and the luminal cellular excrescences observed with scanning and transmission electron microscopy. These observations are similar to those reported in ovariectomized hamsters (Gilloteaux et al., 1992). Further, the gallbladder epithelial cells and nuclei of the older female hamsters demonstrate an accentuated response to a 1 month sex steroid treatment as compared to the younger hamsters for the same treatment duration. These results enable us to hypothesize that changes induced by a short term sex steroid treatment participate in the gallstone nucleation process, while longer duration of the treatments contribute to progressive enlargement and accumulation of gallbladder calculi.