[Effect of aquaporin-1 and sodium channel on pleural fluid transport in mice].

Objective: To investigate the effect of sodium channel and aquaporin-1 on pleural fluid transport.
Methods: Mice were briefly anesthetized, and the pleural space was infused with 0.25 ml of hyperosmolar or isosmolar solution, with terbutaline or amiloride in instilled solution. The mice were treated with either intraperitoneal dexamethasone or intravenous HgCl(2). Mice were euthanized at specified times for measurement of pleural fluid osmolality, volume and (125)I-album in concentration. The rate of pleural fluid filtration and clearance was calculated, which was used to indicate the effect of sodium channel regulator (amiloride and terbutaline) and aquaporin regulator (dexamethasone and HgCl(2)) on pleural fluid transport.
Results: Amiloride decreased the osmotically driven water transport and isosmolar fluid clearance in pleural space (P < 0.05). Terbutaline increased osmotically driven water transport and isosmolar fluid clearance in pleural space (P < 0.05). HgCl(2) decreased, while dexamethasone increased, the osmotically driven water transport in pleural space (P < 0.05). HgCl(2) and dexamethasone had no effect on pleural isosmolar fluid clearance (P > 0.05).
Conclusions: Sodium channel may play a role in osmotic and isosmolar fluid transport in pleural space. Aquaporin-1 may play a role in osmotic fluid transport in pleural space, while having no effect on isosmolar fluid clearance.