Department of Anatomy and Cell Biology
Ph.D.: 1969, University of Kansas, School of Medicine
My research areas have been related to the respiratory and cardiovascular systems. Previously I have studied the innervation and development of the lung, and hypoxia-induced pulmonary and cardiovascular changes. In the lung, a particular cell type, the pulmonary (neuro-)endocrine cell, has been the focus of my interest because of its involvement in lung development and lung cancers.
Current investigation is on the effects of nitric oxide (NO) on the rat lung. NO in the vascular system is produced by endothelial cells and causes vasodilation by inducing relaxation of vascular smooth muscle. In patients with pulmonary hypertension, inhalation of NO causes reduction of pulmonary vascular resistance, as well as improvement in pulmonary blood flow and arterial oxygenation. In such inhalation treatment, NO specifically acts on the pulmonary circulation without causing the complication of systemic hypotension. Despite these benefits, the potential cytotoxicity of NO is not known. In our study, rats were treated with 55 to 60 ppm of NO for 3 weeks, and their lungs were studied with light and electron microscopy. Preliminary observations showed periarterial edema in some NO-treated rats. There is also an increase in the number of these cell types: mast cells in the bronchial epithelium, alveolar macrophages, type II pneumocytes, and neuro-endocrine cells which organize into neuroepithelial bodies. It appears that chronic treatment with NO in the rats may affect activities of multiple cell types in the lung.
Kuen-Shan Hung, Ph.D.