The hypothalamic hormone that stimulates the anterior pituitary to release LH and FSH is:

1. Regulation of testosterone begins outside the testes, in the brain. 2. The hypothalamus releases a pulsatile hormone that signals the anterior pituitary. 3. This hormone is gonadotropin-releasing hormone (GnRH). 4. GnRH binding to pituitary receptors then triggers release of LH and FSH, not the reverse, so testosterone and inhibin (downstream products) are ruled out as the trigger. 5. So GnRH is correct. _Source: OpenStax Anatomy and Physiology (CC BY 4.0), Ch 27 "The Reproductive System", p.1289-1290 §Control of Testosterone_