A conference on Pulmonary Vascular Reactivity was held in Sedalia, Colorado, October 10-12, 1984. The papers and discussion from the meeting are published as part of this and three subsequent issues of Chest. The concept of having a conference on the pulmonary circulation arose because there is no forum devoted to the study of the pulmonary vasculature at present. It is intended that such a conference will occur every second year.
The first meeting was held in honor of Robert E. Grover, M. D., Ph. D. upon his retirement after more than 25 years of active cardiopulmonary research. His documentation of brisket disease in cattle at high altitude is one of the earliest and most complete descriptions of chronic hypoxic pulmonary hypertension. He was one of the first to demonstrate that pulmonary hypertension in congenital heart disease had a reversible vasoconstrictive component. Dr. Grover performed the first measurement of pulmonary arterial pressure in normal North American residents of high altitude and showed that when pulmonary hypertension was present, it was reversible. Dr. Hultgren and he also obtained the first data on pulmonary vascular reactivity in subjects susceptible to high altitude pulmonary edema. He was also involved in the first measurements of pulmonary vascular reactivity in pregnant women. In addition, Dr. Grover instigated or performed studies on a variety of factors which could influence acute or chronic hypoxic pulmonary hypertension (sympathetic activity, prostaglandins, calcium antagonists, endotoxin, acetylcholine, platelets, ethyl alcohol, cold, species and genetic differences. The articles which he has written or co-authored provide a considerable part of our current knowledge of the pulmonary circulation. The conference was organized as a mark of respect for Dr. Grover and his contributions to our understanding of pulmonary vascular reactivity.
The papers presented at the meeting fall into four groups. The first group, published in this issue, concerns the structure and function of the pulmonary vascular endothelium. Particular attention is paid to the interaction of the endothelium with pulmonary vascular smooth muscle and the possible role of endothelial injury in the pathophysiology of pulmonary hypertension. The second group of papers deals with smooth muscle contractility. The specific aspects discussed are calcium kinetics and the effects of hypoxia on energy metabolism and transmembrane electrical potential. The third group analyzes hypoxic pulmonary hypertension in terms of oxygen sensing, the site of vasoconstriction, some possible mechanisms for the vasoconstriction, and the influence of gender on pulmonary vascular reactivity. The final group consists of clinical and experimental studies which examine different facets of pulmonary hypertension. The papers assess the potential benefits and hazards of vasodilator drugs used in the treatment of primary, collagen-vascular, and hypoxic pulmonary hypertension. One report describes the pulmonary vascular changes which occur in sheep when pulmonary hyptertension is induced by repeated injections of endotoxin or indomethacin. Such preparations you may order together with Canadain Neighbor Pharmacy.
This conference was intended to examine recent advances in our knowledge of the functions of smooth muscle and vascular endothelium and apply these insights to the pulmonary vasculature. As a result of current research, more is known about the interaction between endothelium and vascular smooth muscle, the actions of leukotrienes and prostaglandins, the importance of calcium flux involving different sites of calcium sequestration within smooth muscle, and the effects of changes in oxygen tension on cellular energy metabolism. The conference provided an opportunity to integrate this information into our understanding of the mechanisms controlling pulmonary vascular reactivity and the pathologic changes which lead to pulmonary hypertension.
The Pulmonary Circulation Conferences are working meetings, designed to bring together about 35 leading researchers, whose expertise covers biochemistry, pharmacology, physiology, pathology, cardiology and pulmonary medicine. Most of the participants contribute a paper and thus there is no sense of a division between the speakers and the audience. Each paper is followed by an equal time period devoted to discussion of the topic. As the meeting takes place over three days at an isolated conference center, this format promotes cross-fertilization of ideas and collaboration between workers of very different backgrounds. It is our hope that the interchange of concepts and information fostered by this setting will lead to better definition and treatment of the disorders of the pulmonary circulation.