Release of Gonadotropins by Oral Administration of Synthetic LRF or a Tripeptide Fragment of Lrf.

The oral administration to rats of synthetic LRF or of the (amidated) N-terminal tripeptide-fragment of LRF is capable of eliciting a statistically significant increase in plasma LH, the highest dose of LRF also elevating plasma FSH. The highest dose of LRF, as well as the two doses of the tripeptide, produced elevations of plasma LH sustained for at least 1 hr.