Studies of kainate-induced wet-dog shakes in the rat

Four experiments were undertaken to investigate the specificity of kainate-induced wet-dog shakes (WDS) to glutamate and morphine sensitive brain systems. It was shown that intraventricular (icv) administration was much more effective than intracisternal (ic) administration of kainate in producing WDS. This difference was shown not to be due to etherization of the animals during intracisternal injections. Also, like endorphin-induced WDS, kainate-induced WDS were blocked by naloxone. Kainate-induced WDS were substantially reduced by the glutamate receptor blocking agent GDEE. In a study of the relationship between morphine and kainate, behaviors induced by a low dose of morphine (such as grooming and darting movements) were blocked by subsequent administration of kainate. However, kainate-induced WDS were not affected by the morphine treatment.