Does postural asymmetry indicate directionally of rotation in rats: role of sex and handling.

Postural asymmetry of male and female Wistar rats was assessed during 4 tests: (a) tail suspension, (b) tail holding, (c) tail pinch and (d) walking on a narrow path. The tests were conducted prior to and after (+)-amphetamine (1 mg/kg, i.p.) administration. Rotational directionality was assessed in a rotometer. Only in female rats did postural adjustment during the tail-pinch predict with borderline significance the direction of circling prior to and after amphetamine. In both surgically castrated and conjugated estrogen-treated male rats, in sham-castrated and handled males, the tail-pinch test caused the same dominant directionality as rotation under amphetamine. The duplicity of postural tests suggests that there is a multitude of systems controlling and modulating postural response.