That finding suggests estrogen deficiency in aging woman might cause metabolic changes associated with obesity, diabetes and high blood pressure.

Dr. Lourdes Fortepiani of the University of Texas Health Science Center at San Antonio and colleagues studied older intact rats, as well as two groups of rats whose ovaries had been removed. Among the rats with no ovaries, only one group was given estrogen, while the other group remained estrogen depleted.

Rats with no ovaries who did not receive estrogen suffered significantly higher blood pressure, gained more weight and had much higher blood glucose levels than rats from the other two groups. Rats whose ovaries were removed and who were given replacement estrogen had none of the ill effects.

The findings were presented this week in Austin, Texas, during a meeting of The American Physiological Society.