Which hormones antagonize the effect of NO and cause the penis to become flaccid after orgasm?
Norepinephrine is released from the nerve terminals and endothelin is released from endothelial cells in the vasculature, causing vasoconstriction of the vasculature.
Endothelin and norepinephrine
Estrogen and progesterone
Luteinizing hormone (LH) and follicle-stimulating hormone (FSH)
Progesterone and LH
Male Reproductive System