Physiology Which hormones antagonize the effect of NO and cause the penis to become flaccid after orgasm? A Endothelin and norepinephrine B Estrogen and progesterone C Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) D Progesterone and LH 💡 Explanation Which hormones antagonize the effect of NO and cause the penis to become flaccid after orgasm? ✓ Correct Answer: A. Endothelin and norepinephrine