Humoral mediation of radiation-induced motivation in parabiont rats.

Parabiont rat pairs with a skin-vascular anastomosis were used to test for a radiation-induced transferable humoral factor which would motivate aversive conditioning in a nonirradiated (shielded) recipient. The shielded partner, by tasting saccharinflavored fluid shortly after its partner was x-irradiated (360 roentgens), was aversively conditioned to saccharin. This was interpreted as evidence for a humoral motivating factor.