UcnII protects against gentamicin-induced ROS formation. Gentamicin, an aminoglycoside and well-known ototoxic agent, induces significant ROS generation over background (second bar). Pretreat-ment for 1 hr with UcnII, which specifically activates CRF2, protects cells against gentamicin-induced ROS formation (third bar), by normalizing the ROS levels to control values. *P < 0.05, **P < 0.01.