Pharmacokinetics and pharmacodynamics of bupivacaine polylactic acid microspheres in rabbits
- VernacularTitle:布比卡因聚乳酸微球在家兔体内的药代学和药效学
- Author:
Qiang FU
;
Yuan YU
;
Xin-Hua WANG
;
Shen GAO
;
Yanqiang ZHONG
;
Wei WU
;
Xueyin SHI
;
Hongbing YUAN
- Publication Type:Journal Article
- Keywords:
Bupivacaine;
Lactates;
Microsphere;
Pharmacokinetics;
Pharmacology;
Time factors
- From:
Chinese Journal of Anesthesiology
1994;0(03):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the pharmacokinetics and pharmacodynamics of bupivacaine polylactic acid microspheres in rabbits. Methods Sixteen New Zealand rabbits weighing (2.58?0.17) kg were randomly divided into two groups:in group A a bolus of bupivacaine solution 5 mg?kg-1 was injected subcutaneously, in group B a bolus of bupivacaine polylactic acid microspheres 5 mg ? kg-1 was implanted in subcutaneous tissue. Blood samples were obtained for determination of plasma bupivacaine concentration at 5,10,20,30,45 min and 1,2,3,4, 6,8,12,24h after subcutaneous injection in group A and at 0.5,1,2,3,4,5,6,8,12,24,36,48 and 60 h after subcutaneous implantation in group B. Pharmacodynamics study was conducted using a model evaluating the efficacy of regional anesthesia by skin incision and needle pricking. Results In group A plasma bupivacaine concentration peaked quickly at about 0. 34h after subcutaneous injection, then quickly declined and became indetectable in plasma within 12 h. In group B plasma bupivacaine concentration reached a peak much slowly at about 13h after subcutaneous implantation. Cmax was 0.7781 ? 0.3573 ?g?ml-1 significantly lower than that in group A [Cmax = (2.4664 ? 0.7822) ?g?ml-1 ] . The mean retention time (MRT) was 25.2667 ? 2.4857 h, significantly longer than that in group A [MRT= (5.5580 ? 1.3843)h] . Pharmacodynamic study showed that the duration of regional sensory block was significantly longer in group B than that in group A( P
