Testosterone Increases: Sodium Reabsorption, Blood Pressure, and Renal Pathology in Female Spontaneously Hypertensive Rats on a High Sodium Diet

Abstract

Estrogen (E) and testosterone (T) are important in the sexually dimorphic pattern of blood pressure (BP) development. The goal was to examine the effects of endogenous E and exogenous T in the development of hypertension in female spontaneously hypertensive rats (SHR) on a high sodium diet. Female SHR (, 5-week) were divided into four groups: (1) control (), (2) ovariectomized (OVX, ), (3) testosterone implants with intact ovaries (T, ), and (4) ovariectomized + testosterone implants (OVX+T, ). T was given immediately after OVX and replaced every two weeks and they were fed a 3% NaCl diet. BP was measured weekly and plasma norepinephrine (NE) analyzed by HPLC. OVX+T females exhibited the greatest elevation in BP (190 ± 4.0 mmHg) compared to controls at 15 weeks of age (140 ± 3.4 mmHg, ) and a pattern of hypertension development similar to that of male SHR. Females with T treatment showed evidence of glomerulosclerosis. In conclusion, T accelerated the development of hypertension similar to the BP pattern observed in males; the presence of ovaries attenuated the T induced increase in BP; T increased renal sodium reabsorption, and T increased glomerulosclerosis.