Natriuretic and antihypertensive effects of potassium in DOCA-salt hypertensive rats.
The role of a natriuresis in the protective effect of potassium against the development and maintenance of salt-induced hypertension was studied. Uninephrectomized rats showed average systolic pressures of 177 +/- 3 mm Hg after the 28 days of treatment with DOCA while receiving a 1% NaCl solution to drink. The supplements of 0.2 and 1% KCl solution could counteract the blood-pressure raising effect of NaCl in a dose-related fashion: The average pressures on day 28 at these dosages were 131 +/- 3 and 120 +/- 3 mm Hg, respectively. The cumulative sodium retention was significantly less in the KCl-supplemented rats than the DOCA-salt rats. Exchangeable body sodium (sodium "space") at weeks 1 and 4 was significantly increased in the DOCA-salt rats as compared to those in the vehicle-treated rats. But, the potassium supplement could reduce sodium "space" dose-relatedly in the DOCA-salt rats. Overall, there was a close correlation between the systolic pressures and sodium "space" at week 4 (r = 0.811, P less than 0.01). The results suggest that potassium may attenuate the rise in blood pressure during the DOCA-salt treatment in uninephrectomized rats, mainly as a result of inhibition of sodium retention, by increasing renal sodium excretion.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D003864:Depression, Chemical; D003900:Desoxycorticosterone; D004305:Dose-Response Relationship, Drug; D005110:Extracellular Space / Q000187:drug effects; D006973:Hypertension / Q000188:drug therapy* / Q000209:etiology; D007473:Ion Channels / Q000187:drug effects; D007668:Kidney / Q000502:physiology; D008297:Male; D009318:Natriuresis / Q000187:drug effects*; D009392:Nephrectomy; D011188:Potassium / Q000378:metabolism; D011189:Potassium Chloride / Q000008:administration & dosage / Q000627:therapeutic use*; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000378:metabolism; D012965:Sodium Chloride
D007473:Ion Channels; D003900:Desoxycorticosterone; D012965:Sodium Chloride; D011189:Potassium Chloride; D012964:Sodium; D011188:Potassium