Effects of estrogen replacement and L-arginine supplementation on serum levels of nitric oxide in ovariectomized rats

Objective To investigate the effects of estrogen replacement and L-arginine(L-Arg) supplementation on serum levels of nitric oxide in ovariectomized rats.Methods Forty female Wistar rats,3-month-old,were randomly divided into four goups,goup A:sham-ovariectomized rats;group B:ovariectomized rats;group C:ovariectomized rats receiving estrogen replacement therapy;group D:ovariectomized rats receiving estrogen replacement and L-Arg supplementation therapy.Four months later,the concentrations of serum NO,E2 and L-Arg were assayed by nitrate reductase method,RIA and HPLC,respectively.Results(1) The concentrations of serum NO and E2 in group B was decreased significantly compared with other groups(P0.05).(2) The serum levels of E2 had no significant difference in group A,C and D(P0.05).(3) The serum levels of NO had no significant difference in group C and A(P0.05).(4) The serum levels of NO in group D was increased significantly compared with group C(P0.05).Conclusions(1) Estrogen could increase the concentration of serum NO in ovariectomized rats.(2) Exogenous L-Argsupplement could increase the concentration of serum NO in ovariectomized rats.