Intraocular administration of tetramethylpyrazine hydrochloride to rats: a direct delivery pathway for brain targeting?

Intraocular administration of tetramethylpyrazine hydrochloride to rats: a direct delivery pathway for brain targeting? Drug Deliv. 2019 Dec;26(1):841-848 Authors: Mao D, Li F, Ma Q, Dai M, Zhang H, Bai L, He N Abstract The purpose of this study was to compare the pharmacokinetic profile of tetramethylpyrazine hydrochloride (TMPH) in rat plasma and tissues following intravenous (iv), intragastric (ig) and intraocular (io) administration. After io, ig and iv administration of a single dose at 10 mg/kg, tissue and plasma samples drawn from the femoral artery were collected at timed intervals. The concentration of TMPH in the samples was analyzed using high-performance liquid chromatography (HPLC). The area under the concentration-time curve (AUC) and the drug targeting efficiency percentage (DTE(%)) were calculated to evaluate the targeting efficiency of the drug with the three different administration routes. After io administration, TMPH was rapidly absorbed to reach its peak plasma and brain concentration within 5 min. The systemic bioavailability obtained with io administration was greater than that obtained through the ig route (63.22% vs. 16.88%). The AUCt rank order of the iv administration group was AUCkidney >AUCheart >AUCliver >AUCbrain >AUCspleen >AUClung; that of the ig administration group as AUCkidney >AUCliver >AUCheart >AUCspleen >AUCbrain >AUClung; while that of the io administration g...
Source: Drug Delivery - Category: Drugs & Pharmacology Tags: Drug Deliv Source Type: research