title: Influence of polymeric microspheres on the myocardial oxygen partial pressure in the beating heart of pigs.
abstract: Injection of labeled microspheres is an established method in animal models to analyze the capillary organ blood flow at different time points. However, the microspheres can lead to stenoses of the capillary lumen, which might affect tissue oxygen supply. Our study aimed to investigate the influence of repeated injections of microspheres into the left coronary artery on the tissue oxygen partial pressure (pO(2)) in the downstream supplied myocardium of Göttingen minipigs. Tests (n=6 pigs each) were performed with two differently sized microspheres (ø=10 ± 0.1 μm (M10) or ø=15 ± 0.15 μm (M15)) from polystyrene. The pO(2) was measured in the midmyocardium of the left and right ventricle for 6 min continuously after each of five injections (1 × 10(6) microspheres each). There was a time laps of 12 min between each injection. In addition, the influence of the carrier solution was analyzed solely in the identical time frame. pO(2) decreased significantly in the myocardial area supplied by the ramus interventricularis paraconalis after injection of M15 microspheres. In contrast, the application of the M10 microspheres did not change the myocardial pO(2). This finding suggests to use microspheres with diameters not exceeding 10 μm for the coronary blood flow assessment.
authors.affiliation: Center for Biomaterial Development and Berlin-Brandenburg Center for Regenerative Therapies (BCRT), Institute of Polymer Research, Helmholtz Zentrum Geesthacht, Kantstrasse 55, 14513 Teltow, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Hiebl
authors.forename: C
authors.initials: C
authors.lastname: Mrowietz
authors.forename: S
authors.initials: S
authors.lastname: Lee
authors.forename: S
authors.initials: S
authors.lastname: Braune
authors.forename: M
authors.initials: M
authors.lastname: Knaut
authors.forename: A
authors.initials: A
authors.lastname: Lendlein
authors.forename: R P
authors.initials: RP
authors.lastname: Franke
authors.forename: F
authors.initials: F
authors.lastname: Jung
mesh_terms: D000818:Animals; D003331:Coronary Vessels / Q000187:drug effects* / Q000378:metabolism*; D005260:Female; D006321:Heart / Q000187:drug effects; D006352:Heart Ventricles / Q000187:drug effects / Q000378:metabolism; D007269:Injections, Intra-Arterial; D008863:Microspheres; D009206:Myocardium / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D010313:Partial Pressure; D010316:Particle Size; D011137:Polystyrenes / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D013552:Swine; D013556:Swine, Miniature
chemical_list: D011137:Polystyrenes; D010100:Oxygen