Effect of excipient composition on the biocompatibility of XXXX -containing microparticles at the sciatic nerve.

@entity32 @entity1341 @entity4748 @entity4747 @entity35 @entity616
Microparticulate formulations are often used for experimental prolongation of nerve blockade. Here we examine the effect of excipient composition on the biocompatibility of @entity1341 -containing microparticles. Lipid-protein-sugar particles (LPSPs) composed of 3% (1.3-microm diameter) and 60% (4.7-microm diameter) (w/w) @entity4747 ( @entity4748 ) were produced by spray drying, containing 10% (w/w) @entity1341 . @entity35 sciatic nerve blocks with 75 mg of particles produced statistically similar durations of @entity616 [3% (w/w) @entity4748 particles: 301 min; 60% (w/w) @entity4748 particles: 321 min]. Examination of tissues 1 day after injection revealed large particle deposits and acute @entity32 in animals that received 60% (w/w) @entity4748 particles. There were no visible deposits in those that received 3% (w/w) @entity4748 particles, and microscopic @entity32 was reduced. The difference between groups was similar 4 days after injection. Two weeks after injection, there was no particulate mass in either group, and @entity32 had largely resolved. In both groups, moderately severe myotoxicity was seen 1 and 4 days after injection but had largely resolved by 2 weeks. In summary, reduction in particles' @entity4748 content greatly improved biocompatibility without compromising duration of nerve blockade; the improvement was probably attributable to the enhanced rate of particle resorption.
