EFFECT OF ETHER ON SALT AROUSAL OF DRINKING IN HOODED RAT

It was recently observed that ether depresses the salt arousal of drinking in hooded rats. An experiment was conducted to determine whether or not the mechanism mediating salt arousal of drinking responds principally to early rapid increases in serum electrolyte level and if ether depresses drinking by reducing the efficiency of the central mechanism during these early changes. Hooded rats were anesthetized with ethyl ether at different times during and after subcutaneous NaCl injection using as a model data previously obtained for time course of change in serum Na level in hooded rat. Results showed that if ether administration is delayed until after initial rapid increases in serum Na level have taken place, water intake is similar to that of non-etherized controls. Drinking was significantly depressed when ether was given during early changes. Although presently unclear, results suggest that rate of increase in suprathreshold serum Na level is positively related to magnitude of water intake. © 1969.