Leptin lowers blood sugar and insulin in normal mice, but not in mice missing leptin receptors in certain brain cells.

Giving leptin to mice raises their leptin hormone levels to about 80 ng/ml, regardless of whether they have leptin receptors in certain brain cells.

When mice lack leptin receptors in certain brain cells, they become heavier, have higher blood sugar, more insulin, and more leptin hormone than normal mice.

Leptin reduces eating in both normal mice and those missing leptin receptors in certain brain cells, meaning these brain cells aren't needed for leptin's appetite control.

When mice lack leptin receptors in certain brain cells, giving them leptin slightly lowers their blood pressure instead of raising it like in normal mice.

Leptin doesn't change how well mice with missing leptin receptors in certain brain cells regulate their blood pressure through reflexes.