Serum and tissue sodium/potassium changes in estrogen treated female albino rats.

Five control and ten estrogen treated albino rats were studied for changes in sodium and potassium in serum, heart, muscle, uterus and brain. The serum levels of sodium depleted significantly in the estrogen treated rats. Of the tissues studied, only uterus and brain had significantly sodium retention effect. The potassium levels on the other hand decreased significantly, both in serum and tissues following treatment with estrogen.

Continuous illumination and oogenesis in albino rabbits.

Photo periodism is probably a phenomenon of natural selection. The critical period of ovulation can be adjusted to the environmental condition such as exposure to continuous illumination (LL) at constant temperature. Many investigators have also observed that blindness in girls causes early menarche while opposite results are obtained in rats. The present study was based upon the changes in circadian rhythm of ovaries of albino rabbits, by exposing the animals to continuous illumination through an electric bulb of 100 watt kept at one metre distance, at 37 degrees C, vaginal smear showed constant estrus. It was observed that degenerative changes started appearing in the histology of ovaries from first week of experiment. Degenerative changes were gradual and led to complete metaplasia or atrophy of ovary.