simultaneous or sequential injection of 250 ng gonadotrophin releasing hormone ( gnrh ) and 25 micrograms oestradiol benzoate , with luteinizing hormone ( lh ) measurements at 0 , +20 min ( after gnrh ) and +16 h ( after oestradiol ) , enabled investigation of the positive feedback effects on the hypothalamus and pituitary .
C0023610
gnrh
C0020663
hypothalamus