Neuropharmacological mechanisms of emesis. I. Effects of antiemetic drugs on motion- and apomorphine-induced pica in rats
Takeda, N.; Hasegawa, S.; Morita, M.; Horii, A.; Uno, A.; Yamatodani, A.; Matsunaga, T.
Methods and Findings in Experimental and Clinical Pharmacology 17(9): 589-590
1995
ISSN/ISBN: 0379-0355 PMID: 8786672 Document Number: 440178
The effects of diphenhydramine, domperidone, ondansetron, and diphenidol on motion- and apomorphine-induced pica (ie., kaolin ingestion) in rats as the measure analogous to emesis in other species were examined Diphenhydramine (10 and 20 mg/kg) and diphenidol (30 mg/kg) inhibited kaolin intake induced by 60-min double rotation, while domperidone and ondansetron did not. Kaolin intake induced by apomorphine (10 mg/kg) was inhibited by domperidone (2 mg/kg) and diphenidol (30 mg/kg), but not by diphenhydramine or ondansetron. These findings suggest that the emetic pathways through the inner ear (double rotation) and the chemoreceptor trigger zone (apomorphine) are pharmacologically independent and are mediated by histamine H-1 receptors and dopamine D-2 receptors, respectively. Diphenidol may inhibit a common locus of emesis.