Changes in ingestive behaviors and body weight following intracranial application of 17 alpha-estradiol.

The present experiment was conducted to determine if central implants of 17 alpha-estradiol could influence food intake, water intake, and body weight in ovariectomized rats. A total of fifteen animals were fitted with bilateral guide cannulae in the paraventricular nucleus (PVN) and stimulated unilaterally with cholesterol and 17 alpha-estradiol in each side of the brain. Compared with cholesterol treatment, 17 alpha-estradiol implants in the PVN significantly lowered food intake and body weight but did not affect water intake. These findings indicate that the PVN is a brain region responsive to the effects of 17 alpha-estradiol on feeding behavior, and support the hypothesis that the effects of estrogens on ingestive and reproductive behaviors are organized separately within the brain.