The effects of ethanol upon hydric balance and arterial pressure in rats: folic acid as a possible hypotensor.
OBJECTIVE
Chronic alcohol intake is related to hypertension. There are, however, few studies concerning the effect of ethanol upon hydric balance in relation to arterial pressure. Folic acid intake has beneficial effects upon the cardiovascular system decreasing hyperhomocysteinemia, however, more studies imply that it is related with other mechanisms. Therefore, we have studied the effects of chronic alcohol intake (30% v/v) upon hydric-saline balance and hypertension and have found that dietary supplementation with folic acid (8 mg/kg) improves the above parameters.


METHODS
Our study used four experimental groups of rats: control, alcohol, alcohol with folic acid and control with folic acid. In all cases we measured the clearance of Na(+), K(+) and aldosterone; osmolarity in urine, liquid and solid ingestion; homocysteine levels in serum; cardiac frequency and arterial blood pressure.


RESULTS
The alcohol intake increases serum aldosterone and homocysteine, which is reflected in an increase in arterial blood pressure. In addition, we have found that alcohol intake reduces both liquid and solid ingestion (causing a malnourishment status), the clearance of creatinine, aldosterone, Na(+) and K(+), and the ratio ClNa(+)/ClCr; it also increases urine osmolarity. Folic acid supplementation increases the clearance of Na(+) and the ratio ClNa(+)/ClCr.


CONCLUSIONS
Folic acid intake improves the hypertension provoked by alcohol by increasing the aldosterone clearance, drastically reducing the serum levels of this hormone and thus its hypertensor effect.
Department of Physiology and Zoology, University of Seville, Seville, Spain.
M J
MJ
Barrero
M L
ML
Ojeda
J
J
Díaz Castro
F
F
Nogales
M L
ML
Murillo
O
O
Carreras
D000428:Alcohol Drinking / Q000009:adverse effects* / Q000503:physiopathology; D020751:Alcohol-Induced Disorders / Q000150:complications / Q000188:drug therapy*; D000450:Aldosterone / Q000097:blood / Q000652:urine; D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology / Q000627:therapeutic use*; D003404:Creatinine / Q000097:blood / Q000652:urine; D019587:Dietary Supplements; D000431:Ethanol / Q000008:administration & dosage / Q000009:adverse effects*; D005492:Folic Acid / Q000494:pharmacology / Q000627:therapeutic use*; D020138:Hyperhomocysteinemia / Q000188:drug therapy; D006973:Hypertension / Q000139:chemically induced / Q000188:drug therapy*; D007668:Kidney / Q000187:drug effects; D008297:Male; D011188:Potassium / Q000097:blood / Q000652:urine; D051381:Rats; D017208:Rats, Wistar; D012964:Sodium / Q000097:blood / Q000652:urine; D014882:Water-Electrolyte Balance / Q000187:drug effects*
D000959:Antihypertensive Agents; D000431:Ethanol; D000450:Aldosterone; D005492:Folic Acid; D012964:Sodium; D003404:Creatinine; D011188:Potassium