Elevated blood pressure in spontaneously hypertensive rats consuming a high sucrose diet is associated with elevated angiotensin II and is reversed by vanadium.
OBJECTIVE
To determine the changes in serum angiotensin II (Ang II) and endothelin-1 levels induced by vanadium treatment of sugar-fed rats in order to investigate the relationship between changes in blood pressure and Ang II and endothelin-1 levels.


METHODS
Male spontaneously hypertensive rats (SHR) were fed starch (control), sucrose, and sucrose plus vanadium compounds at various concentrations. The systolic blood pressure of the rats was estimated by tail-cuff plethysmography. Serum Ang II and endothelin-1 levels were measured by radioimmunoassay.


RESULTS
There were increases in systolic blood pressure (by 8%) and in serum Ang II (by 20%) in sucrose-fed SHR compared with control. In sucrose plus vanadium-fed SHR, the lowering of the systolic blood pressure (by 11-16% of the sucrose-fed value) was accompanied by a significant decrease in Ang II levels (by 25-60% of the sucrose-fed value) and an increase in endothelin-1 level (by 61-76% of the sucrose-fed value).


CONCLUSIONS
That Ang II levels are elevated in sucrose-induced hypertension and decreased after vanadium therapy suggests that the renin-angiotensin system plays a role in the induction of hypertension in this model. On the other hand, the elevation of endothelin-1 levels associated with a decreased systolic blood pressure might be secondary to vanadium stimulation of endothelial cells. The data suggest that endothelin-1 is not involved in sugar-induced elevations of the blood pressure.
Shi
S J
SJ
Department of Medicine, Georgetown University Medical Center, Washington, D.C. 20007, USA.
Preuss
H G
HG
Abernethy
D R
DR
Li
X
X
Jarrell
S T
ST
Andrawis
N S
NS
D000804:Angiotensin II / Q000097:blood*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001835:Body Weight; D019422:Dietary Sucrose / Q000494:pharmacology*; D019332:Endothelin-1 / Q000097:blood; D006973:Hypertension / Q000097:blood*; D008297:Male; D011863:Radioimmunoassay; D051381:Rats; D011918:Rats, Inbred SHR; D014639:Vanadium / Q000494:pharmacology*
D019422:Dietary Sucrose; D019332:Endothelin-1; D014639:Vanadium; D000804:Angiotensin II