An escape phenomenon from water and sodium retention induced by propranolol in rats

Summary Rats given a daily dose of propranolol 45 mg/kg b.wt retain water and sodium for 4 days, escaping during the 5th and 6th days in which their excretions are larger than basal values. Afterwards, in the period studied, they make a new retention and clearing is less accentuated. No relationship could be found between these retentions and plasma renin activity or renal renin content.Acknowledgments. The authors thank Mrs Inmaculada Millás for excellent technical assistance and Maria Isabel Navajos for secretarial help.