Drug delivery for intracerebral of flunarizine hydrochloride after intraocular administration in rats

OBJECTIVESIntraocular administration was a commonly route of administration in clinic, but most of the intraocular administration was only used to treat local ocular diseases. Based on the particularity of the ocular structure, this article mainly explored the feasibility of flunarizine hydrochloride in the treatment of ischemic cerebral vascular diseases (ICVD) by intraocular administration. METHODSA total of 150 SD rats were randomly divided into 3 groups with intraocular, intragastric, and intravenous administration, respectively. The doses were 14 mg/kg for intraocular and intragastric groups and 5 mg/kg for intravenous group. The plasma and brain concentration of flunarizine hydrochloride were analyzed by high performance liquid chromatography (HPLC). Main pharmacokinetic parameters and absolute bioavailability were evaluated. Brain targeting of flunarizine hydrochloride through intraocular administration was studied by drug targeting index of brain (DTIbrain). RESULTSMaximum contentration (Cmax) and area under the time-concentration curve from o to t (AUC0-t) of plasma after intraocular administration were significantly higher than those of plasma after intragastric administration (both P