Presence of sodium transport inhibiting factor in dog plasma during volume expansion

Summary Plasma dialysates from volume-expanded dogs (E) were compared directly to dialysates from the same dogs when hydropenic. In a double-blind study, E caused relative inhibition of short-circuit current in toad urinary bladder. We therefore confirm the presence of a sodium transport inhibiting factor in plasma of volume-expanded dogs.Acknowledgments. This study was supported by the Philadelphia Veterans Administration Hospital (103.6M). We would like to thank the laboratory of Dr V. Buckalew at Bowman Gray School of Medicine, Winston-Salem, North-Carolina, for preparation of plasma dialysates; G. Huber and E. Fink for technical assistance and K. Conrad for secretarial assistance.