title: Distribution of domperidone into the rat brain is increased by brain ischaemia or treatment with the P-glycoprotein inhibitor verapamil.
abstract: Domperidone (DOM), a peripheral dopamine D2 receptor antagonist, is a substrate of P-glycoprotein (P-gp). Therefore, the transport of DOM into the brain may be restricted by P-gp function at the blood-brain barrier, and when the function of P-gp is impaired by ATP depletion under conditions of brain ischaemia (e.g. cerebral thrombosis), side-effects may be induced as a result of increased distribution of DOM into the brain. In this study, we investigated the effects of brain ischaemia and verapamil, a P-gp inhibitor, on the permeability coefficient-surface area product (PS values) of DOM across the blood-brain barrier by using an in-situ rat brain perfusion technique. The PS values of DOM were increased 3.4- and 3.6-fold after brain ischaemia for 10 and 20 min, respectively. Furthermore, co-administration of verapamil significantly increased the PS values of DOM by 42.6- and 43.3-fold in the normal and ischaemia groups, respectively. Brain vascular volume was not affected by ischaemia or verapamil. These results show that the transport of DOM into the brain is restricted by P-gp and that the brain distribution of DOM can be increased by cerebral ischaemia or co-administration of a P-gp inhibitor.
authors: Department of Biopharmaceutics, Medico-Pharmaceutical Sciences, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka, Japan.
authors: Yukihiko
authors: Y
authors: Dan
authors: Hideyasu
authors: H
authors: Murakami
authors: Noriko
authors: N
authors: Koyabu
authors: Hisakazu
authors: H
authors: Ohtani
authors: Yasufumi
authors: Y
authors: Sawada
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000037:antagonists & inhibitors; D000818:Animals; D001692:Biological Transport; D001812:Blood-Brain Barrier / Q000187:drug effects*; D001921:Brain / Q000098:blood supply / Q000378:metabolism*; D002545:Brain Ischemia / Q000378:metabolism / Q000503:physiopathology*; D002199:Capillary Permeability / Q000187:drug effects; D004294:Domperidone / Q000493:pharmacokinetics*; D018492:Dopamine Antagonists / Q000493:pharmacokinetics*; D008297:Male; D010477:Perfusion; D051381:Rats; D017208:Rats, Wistar; D014700:Verapamil / Q000494:pharmacology*
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D018492:Dopamine Antagonists; D004294:Domperidone; D014700:Verapamil