Dietary vitamin E supplementation lowers blood pressure in spontaneously hypertensive rats.
In spontaneously hypertensive rats (SHRs) excess endogenous aldehydes bind sulfhydryl groups of membrane proteins, altering membrane Ca2+ channels and increasing cytosolic free calcium and blood pressure. The thiol compound, N-acetyl cysteine, normalizes elevated blood pressure in SHRs by binding excess endogenous aldehydes. Vitamin E increases tissue glutathione levels--a storage form of cysteine. The aim of the present study was to investigate whether a dietary supplementation of vitamin E lowers blood pressure and prevents renal vascular changes by normalizing tissue aldehyde conjugates and cytosolic [Ca2+] in SHRs. Starting at 12 weeks of age, animals were divided into three groups of six animals each. Animals in the WKY-control group and SHR-control group were given a normal diet and the SHR-vitamin E group a diet supplemented with vitamin E (34 mg/ kg feed) for the next 9 weeks. After 9 weeks, systolic blood pressure, platelet [Ca2+]i, and liver, kidney and aortic aldehyde conjugates were significantly higher in SHR controls as compared to WKY controls and the SHR-vitamin E group. SHR-controls also showed smooth muscle cell hyperplasia in the small arteries and arterioles of the kidney. Dietary vitamin E supplementation in SHRs lowered the systolic blood pressure, cytosolic [Ca2+], tissue aldehyde conjugates and attenuated adverse renal vascular changes.
D000284:Administration, Oral; D000447:Aldehydes / Q000032:analysis; D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology / Q000627:therapeutic use; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism; D001794:Blood Pressure / Q000187:drug effects*; D001835:Body Weight / Q000187:drug effects; D002118:Calcium / Q000097:blood; D019587:Dietary Supplements; D004327:Drinking Behavior / Q000187:drug effects; D004435:Eating / Q000187:drug effects; D006973:Hypertension / Q000188:drug therapy; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D013997:Time Factors; D014810:Vitamin E / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use
D000447:Aldehydes; D000959:Antihypertensive Agents; D014810:Vitamin E; D002118:Calcium