Metformin treatment reduces Glut2 expression in the liver. (A) Urinary sodium and potassium excretion and plasma glucose levels in vehicle- and metformin-treated rats. (B) Immunohistochemical staining demonstrates that metformin treatment decreases abundance of hepatic Glut2, a key glucose transporter involved in glucose release (40x). Scale bar = 50 μm. Shown on the right is summary graph for Glut2 relative abundance (**p < 0.01 relative to vehicle).