Spontaneous nitroblue-tetrazolium reactivity is correlated to the distribution of pmngs between rat pulmonary and systemic circulation . Wikstr[diaeresis]om, T., M. Braide, U. Bagge, and B. Risberg. Department of Surgery, Anatomy and Cell Biology, University of G[diaeresis]oteborg and Department of Surgery, University of Lund, Sweden, Experiments performed at: Department of Anatomy & Cell Biology, University of G[diaeresis]oteborg, Medicinaregatan 3, S-413 90 G[diaeresis]oteborg, Sweden.
APStracts 2:0164H, 1995.
The rat systemic and pulmonary vascular transit times of radiolabelled polymorphonuclear granulocytes (polys) and mononuclear leukocytes (monos) (111In) in relation to those of erythrocytes (51Cr) were measured under physiological conditions. Results were also expressed as "circulating" pool and "marginated" pool of the two leukocyte fractions, and it was investigated whether the degree of spontaneous granulocyte activation, measured with the nitroblue tetrazolium reduction (NBT) test, was of importance for the retention of polys in the lungs. The measured mean vascular transit was similar for monos and polys and several times slower than that of the erythrocytes in the pulmonary (x17.4) and the systemic (x4.1) vascular beds. The percentage NBT-positive cells was less than 10% in most animals, indicating a low level of spontaneous granulocyte activation. Increasing levels of NBT-positive cells correlated with a redistribution of granulocytes from the systemic "marginated" cell pool to the pulmonary "marginated" cell pool. Microscopic evaluation of sections from embedded lung tissue biopsies, obtained after intravital staining of the leukocytes, confirmed the isotope data on pulmonary transit.

Received 18 March 1994; accepted in final form 19 April 1995.
APS Manuscript Number H260-4.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on  2 May 1995.