Effect of in vivo treatment of different doses of GnRH-Ag on circulating steroids and expression of steroid receptors in the ovaries of mice. A) Circulating progesterone, B) circulating estradiol concentration; C) western blot analyses of PR and ER-α protein. Bar showing densitometric analyses of D) PR and E) ER-α blots (n = 3). Mice treated with normal saline served as control. Values are ± S.E.M. * or # Values are significantly (P < 0.01) different versus control.