Effect of histamine on the electrophysiology of the human parietal pleura

Histamine is involved in the pathogenesis of numerous diseases and regulates the permeability of different tissues. The aim of this study is to investigate the effects of histamine on the electrophysiology of human parietal pleura and the underlying mechanisms involved. Pleural specimens were obtained from patients subjected to thoracic surgery and were mounted in Ussing chambers. Histamine solutions (1μM to 1mM) were applied in native and pretreated specimens with dimetindene maleate, cetirizine, ranitidine, amiloride and ouabain. Trans-mesothelial resistance was determined (RTM). Histamine induced a rapid RTM increase on the mesothelial (p=0.008) and a decrease on the interstitial surface (p=0.029). This effect was dose-dependent and was totally abolished by dimetindene maleate, cetirizine and amiloride and partially by ranitidine and ouabain. Histamine induces acute electrochemical changes in human pleura mainly via interaction with the H1 and partially with the H2 histamine receptors. It also interferes with trans-cellular permeability and therefore may participate in pleural fluid recycling.