Endothelin-1 causes sequential trapping of platelets and neutrophils in the pulmonary microcirculation in rats. Helset, Elin, Sigurd Lindal, Randi Olsen, Reidar Myklebust, and Leif J[stod]orgensen. Department of Anesthesiology, Institute of Clinical Medicine, and Department of Morphology, Institute of Medical Biology, University of Troms[stod]o, Troms[stod]o, Norway
APStracts 3:0079L, 1996.
E.Helset, S.Lindal, R. Myklebust, R. Olsen and L.J[stod]orgensen. Endothelin-1 causes a sequential trapping of platelets and leukocytes in the pulmonary circulation. ----------- We previously showed that endothelin-1 (ET-1) causes accumulation of leukocytes in the pulmonary microvasculature, and increases vascular permeability in isolated rat lungs provided the presence of leukocytes in the perfusate. In the present study we examined the time-sequence for morphological changes induced by ET-1 in rat alveolar tissue. For this purpose we used morphometric analysis based on lung transmission electron micrographs. Morphometry was performed by point counting, and data expressed as relative volume density. ET-1, at 0.06, 0.6 and 6 nmol/kg was infused into the internal jugular vein, and the animals were killed at certain points of time. The lungs were fixed by endotracheal instillation of McDowells fixative.

Received 28 March 1995; accepted in final form 30 April 1996.
APS Manuscript Number L202-5.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 5 June 96