Chronic estrogen treatment modifies insulin-induced insulin resistance and hypertension in ovariectomized rats.
BACKGROUND
Gender differences have been found in the development of hypertension. The role of estrogen in the association between hyperinsulinemia/insulin resistance and hypertension was investigated in an insulin-induced, insulin-resistant, and hypertensive model.


METHODS
Ovariectomized or sham operated female Wistar rats were chronically treated with insulin and/or estrogen via subcutaneous implants (insulin, 2 U/day; 17beta-estradiol 0.5 mg/pellet, 60-day release). Systolic blood pressure was monitored at weeks 0, 3, and 6. At week 7, an oral glucose tolerance test was performed.


RESULTS
Ovariectomy resulted in the development of insulin resistance and blood pressure elevation in chronically insulin-treated female rats. Chronic estrogen treatment prevented the elevation in blood pressure and the development of insulin resistance.


CONCLUSIONS
The results indicate that chronic estrogen treatment modifies the insulin-induced hypertension by increasing insulin sensitivity in ovariectomized rats.
Song
Dongzhe
D
Division of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, University of British Columbia, 2146 East Mall, Vancouver, British Columbia V6T 1Z3, Canada.
Arikawa
Emi
E
Galipeau
Denise M
DM
Yeh
Jennifer N
JN
Battell
Mary L
ML
Yuen
Violet G
VG
McNeill
John H
JH
D000704:Analysis of Variance; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D005951:Glucose Tolerance Test; D006973:Hypertension / Q000139:chemically induced / Q000503:physiopathology* / Q000517:prevention & control; D007004:Hypoglycemic Agents / Q000494:pharmacology; D007328:Insulin / Q000097:blood / Q000494:pharmacology*; D007333:Insulin Resistance; D010052:Ovariectomy; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D001786:Blood Glucose; D004967:Estrogens; D007004:Hypoglycemic Agents; D007328:Insulin