title: Exercise induced sodium conservation: changes in plasma renin and aldosterone.
abstract: Previous studies have demonstrated a renal Na+ conservation during repeated days of exercise in the heat. The present study was intended to describe the role of plasma aldosterone (PAC) in reducing urine Na+ losses during and after 60 min of exercise (60% VO2max) in a warm environment (30 degrees C, 50-53% relative humidity). Additional measurements were made of plasma renin activity (PRA) in an effort to demonstrate the relationship between PRA and PAC. This study shows that a single bout of exercise can significantly reduce urine Na+, Cl-, and H20 excretions for up to 48 hours. Both PRA and PAC were significantly elevated during and immediately after exercise and returned to the pre-exercise level within 6-12 hours of recovery. Subsequently, ingestion of 180 mEq of Na+ each day with ad libitum water intake results in an increased NaCl storage and an expansion of the extracellular volume.
mesh_terms: D000328:Adult; D000450:Aldosterone / Q000097:blood*; D001798:Blood Proteins / Q000032:analysis; D001835:Body Weight; D002713:Chlorine / Q000097:blood / Q000652:urine; D004231:Diuresis; D006358:Hot Temperature; D006801:Humans; D008297:Male; D009994:Osmolar Concentration; D005082:Physical Exertion; D010953:Plasma Volume; D011188:Potassium / Q000097:blood / Q000652:urine; D012083:Renin / Q000097:blood*; D012964:Sodium / Q000097:blood / Q000378:metabolism* / Q000652:urine; D014556:Urine
chemical_list: D001798:Blood Proteins; D000450:Aldosterone; D002713:Chlorine; D012964:Sodium; D012083:Renin; D011188:Potassium