title: Preparation and pharmacokinetics in beagle dogs of once-a-day tetramethylpyrazine phosphate sustained-release pellets.
abstract: In this study, once-a-day tetramethylpyrazine phosphate (TMPP) sustained-release pellets were successfully prepared. The pellets cores were carried out in extrusion-spheronization machine and then coated in fluidized-bed. To optimize cumulative release profile, two different coating systems with the same the TMPP pellets cores were employed. The first coating system consisted of surlease, containing HPMC E5 (0.1% w/w), i.e., P1. The second coating system only consisted of surlease, i.e., P2. The two kinds of coating systems were both given coating levels in terms of weight gain of 10%. The resulted once-a-day TMPP sustained-release pellets (OTSP), the mixture of P1 and P2 with the weight proportion of 1:1, were filled in a capsule (150 mg TMPP/capsule). The relative bioavailability of OTSP was studied in six beagle dogs after oral administration using a commercial TMPP tablets as a reference. The C(max) and T(max) for OTSP and TMPP tablets were 213.06 ng/mL, 2.50 h and 3402.13 ng/mL, 0.33 h, respectively and the relative bioavailability of P3 was 97.18% compared with TMPP tablets. Based on the results, it was indicated that TMPP sustained-release pellets and TMPP conventional tablets were bioequivalent.
authors.affiliation: Department of Pharmacy, China Pharmaceutical University, Nanjing, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Yanyu
authors.forename: Ping
authors.initials: P
authors.lastname: Qineng
authors.forename: Su
authors.initials: S
authors.lastname: Zhigui
authors.forename: Li
authors.initials: L
authors.lastname: Hongying
authors.forename: Niu
authors.initials: N
authors.lastname: Jiangxiu
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001682:Biological Availability; D002121:Calcium Channel Blockers / Q000737:chemistry / Q000493:pharmacokinetics*; D003692:Delayed-Action Preparations / Q000737:chemistry / Q000493:pharmacokinetics; D004285:Dogs; D008297:Male; D023421:Models, Animal; D010710:Phosphates / Q000493:pharmacokinetics; D010975:Platelet Aggregation Inhibitors / Q000737:chemistry / Q000493:pharmacokinetics*; D011719:Pyrazines / Q000737:chemistry / Q000493:pharmacokinetics*; D011897:Random Allocation; D013607:Tablets / Q000493:pharmacokinetics; D014665:Vasodilator Agents / Q000737:chemistry / Q000493:pharmacokinetics*
chemical_list: D002121:Calcium Channel Blockers; D003692:Delayed-Action Preparations; D010710:Phosphates; D010975:Platelet Aggregation Inhibitors; D011719:Pyrazines; D013607:Tablets; D014665:Vasodilator Agents; C017953:tetramethylpyrazine