Gonadal effects on plasma ACE activity in mice

Angiotensin-converting enzyme (ACE) regulates blood pressure and is an important target in the management of hypertension. Hypertension is a gender biased disease. Plasma ACE activity is significantly higher in male mice (309 U/l) than female mice (237 U/l) and is reduced significantly upon gonadectomy to 224 and 209 U/l, respectively. Although, the gonads influence plasma ACE activity in both male and female mice, the effect is more pronounced in male mice. Plasma ACE is derived from the cleavage of tissue ACE and lung has the highest concentration of tissue ACE. However, lung ACE activity is not gender dimorphic but increases significantly upon gonadectomy in both male and female. ACE mRNA level in the lung is not influenced by gender or gondaectomy. Therefore, the gonads affect plasma ACE activity by influencing cleavage of tissue ACE to plasma ACE and/or decrease stability of plasma ACE in gonadectomized mice is mediated.