Introduction and Methods:To determine the effect of 2-methoxyestradiol on Systolic Arterial Pressure (PAS) and myocardial arterial remodelling in a gender rat model of spontaneous hypertension.The experiments were performed in five groups of Spontaneously Hypertensive Rats: intact female, male, ovariectomized, ovarectomized plus 2-methoxyestradiol (10 mg/Kg.h in an Alzet osmotic pump) and male plus 2-methoxyestradiol. Ovarectomy and osmotic pump placement were performed at 10 week. From 10 week to 18 PAS was measured weekly by pletismography. At 18 week of age, the heart and the mesenteric arteries were excised. Structural changes in coronary arteries (wall-to-lumen ratio) were quantified by the image analyzer software (Zeiss K300) and an Inmunoblotting was performed on mesenteric arteries for e-NOS expression measurement.

Results and conclusions:We found that there are gender significant differences in PAS (169.49+4.16 mmHg in female and 193.52+1.03 in male) and in vascular remodelling (0.22+0.02 in female and 0.40+0.05 in male).Ovarectomy induced a significant higher increase in blood presure achieving 175.89+2.45 mmHg at the end of the protocol and a greater vascular remodelling compare to intact rats. The treatment with 2-methoxiestradiol prevented the higher increase in blood pressure in female ovarectomized rats and in males rats. Vascular remodelling was significantly attenuated by treatment with 2-methoxyestradiolin both two groups.These results suggest that the 2-metoxyestradiol reduces gender differences in the evolution of hypertension and myocardial arterial remodeling and also prevents the higher increase of arterial pressure and vascular remodeling induced by ovarectomy.