Effects of Spontaneous Hemolysis, Purified, and Chemically Modified Hemoglobin on Endothelium-Dependent Vasodilation and Baseline Coronary Hindrance in Rabbit Hearts Perfused With and Without Red Cells.
Abstract
Hemoglobin (Hb) solutions being developed as red cell substitutes may have vasoconstrictor activity. We tested whether different coronary constrictor activities of certain Hb solutions were due to differential inhibition of endothelium-dependent vasodilation. In buffer-perfused rabbit hearts with constant coronary flow, Hb increased coronary resistance as indicated by increased perfusion pressure. Purification or chemical modification of Hb Sinificantly decreased coronary vasoconstriction. The maximum increase of perfusion pressure 56 +/- 6 mm Hg for unmodified Hb prepared by ultrafiltration, 32 equal 2 mm Hg for HPLC-purified Hb Ao, and 21 equal 4 mm Hg for Hb crosslinked with bis 3,5-dibromo- salicyl fumarate (DBBF-Hb). Endothelium-dependent coronary dilation was tested in hearts perfused with: a) red cells with supernatant Hb concentrations of 60-650 mg/dl due to spontaneous hemolysis), b) red cells with 1.6 equal 0.4 g/dl Hb Ao, and c) 5.5 g/dl DBBF-Hb without red cells.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 21, 1993
- Accession Number
- ADA360172
Entities
People
- C. R. Valeri
- C. S. Apstein
- G. Cassidy
- W. M. Vogel
Organizations
- Boston University