title: Use of immobilized L-asparaginase in acrylic microparticles in an extracorporeal hollow-fiber dialyzer.
abstract: L-asparaginase was immobilized under aseptic conditions in spherical microparticles of polyacrylamide. To avoid direct contact between blood and enzyme, we have applied the immobilized L-asparaginase in microparticles on the outer surface of the capillary fibers of a hemofilter. The hemofilters were very efficient in the transformation of L-asparagine to L-aspartic acid, both in vitro and in vivo. L-Asparagine in buffer (50 microM in 5 liters) was converted to L-aspartic acid within 60 min after circulation through a hemofilter containing 2000 I.U. of L-asparaginase. Circulating L-asparagine in healthy sheep (about 40-50 microM was reduced to low levels after 2 to 3 hr of perfusion with a unit containing 2000 I.U. of L-asparaginase. The reduction persisted for 3 to 4 hr after terminated treatment. Repeated, extracorporeal treatments in sheep showed that the L-asparagine decrease induced an increased resynthesis of L-asparagine, probably due to the action of the L-asparagine synthetase.
mesh_terms: D000180:Acrylic Resins; D000818:Animals; D001215:Asparaginase / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*; D001216:Asparagine / Q000097:blood; D001224:Aspartic Acid / Q000097:blood; D001769:Blood; D008863:Microspheres; D010477:Perfusion; D006435:Renal Dialysis / Q000379:methods*; D012756:Sheep; D014462:Ultrafiltration; D000099166:Polyacrylamides
chemical_list: D000180:Acrylic Resins; D001215:Asparaginase; D001216:Asparagine; D001224:Aspartic Acid; D000099166:Polyacrylamides