RESPONSES OF RANA TEMPORARIA AND RANA ESCULENTA TO PROLONGED EXPOSURE TO A SALINE ENVIRONMENT

1. 1. Rana temporaria and Rana esculenta can survive immersion in 0·7% saline for many weeks, despite increased plasma Na and osmolal concentrations. 2. 2. An increased plasma urea concentration-with decreased urinary urea concentration in the first few days-is considered as a physiological response to osmotic stress. 3. 3. Changes in net Na efflux and skin potentials, in vivo, are related to changes in renal and cutaneous transport of Na. 4. 4. The Pitressin-induced increment in osmotic water flow in the urinary bladder, in vitro, is reduced. © 1969.