In rats, male kidneys make more endothelin-1 when they eat salt—but in humans, it’s the opposite: female kidneys make more. This shows we can’t just assume animal results apply to people.

When women who are healthy and not menopausal eat a lot more salt for 10 days, their kidneys release more of a substance called endothelin-1 to help flush out the extra salt—but men’s kidneys don’t do this same thing.

Women’s kidneys respond to eating a lot of salt by making more endothelin-1—a substance that helps flush out salt—but men’s kidneys don’t make more of it, even when they eat the same amount.

In rats with kidney problems, blocking a specific protein receptor stops kidney damage caused by acidic diets, showing this receptor is important for acid-related kidney harm.