The angiotensin AT(1) receptor antagonist, losartan, induces barrel rotation in the rat

Intracerebroventricular injections of [Arg(8)]vasopressin (500 ng/rat) or e ndothelin-l (70 ng/rat) into the right lateral ventricle induced rotation a long the long axis of the body (barrel rotation) in rats. Losartan (10-200 mu g/rat), an angiotensin AT(1) receptor antagonist, also evoked barrel rot ation, which was not inhibited by vasopressin and endothelin receptor antag onists. However, barrel rotation was not observed after injections of high doses of another angiotensin II receptor antagonist, [Sar(1),Ile(8)]angiote nsin II (100 mu g/rat), or after angiotensin LT (10 mu g/rat). The results indicate that losartan does evoke barrel rotation which may be not mediated via vasopressin and endothelin receptors. (C) 1998 Elsevier Science B.V. A ll rights reserved.