Inhibitory effects of estrogen on stimulated salt appetite in rats.

Adult male rats consumed 50-150% more 0.5 M NaCl solution than females did during a 7-hr drinking test when robust salt appetite was elicited by dietary sodium deprivation for 8 days, daily injections of deoxycorticosterone, or adrenalectomy followed by 2 days of sodium deprivation. In contrast, male rats drank much less saline after systemic treatment with the natriuretic agent furosemide, adrenalectomy followed by 1 day of sodium deprivation, or sc treatment with colloid solution after 2 days of sodium deprivation, and female rats drank comparably small volumes. Conversely, 30-day-old prepubescent male and female rats showed equally robust salt appetites after 8 days of sodium deprivation. These and other findings support an inhibitory role of estrogen on salt appetite in rats, which appears to occur only when the appetite is especially pronounced.