Effect of histamine and H1 and H2 receptors antagonists on carbachol-induced wet-dog shakes in rats

Intracerebroventricular administration of carbachol chloride induced a characteristic wet-dog shake response in rats. Histamine did not change the number of wet-dog shakes during a 60 min observation but intensified the number of episodes in the first 30 min of the experiment. Antagonists of H1 (thenalidine and antazoline) and H2 (cimetidine and ranitidine) receptors, attenuated carbachol-induced wet-dog shakes. It may be suggested that inhibition of the central histaminergic structures decreased central cholinergic activity.