PRESENCE OP CORTICOTROPIN RELEASING FACTOR-LIKE IMMUNOREACTIVITY IN HYPOPHYSIAL PORTAL BLOOD

Abstract

Hypophysial portal blood was collected from pentobarbital anesthetized male rats, and the content of corticotropin releasing factor-like immunoreactivity (CRF-LI) was measured using an RIA developed for synthetic ovine CRP. The concentration of CRP-LI in portal plasma was 104–;9 ± 9.7 pM. This concentration is in the range which has been shown to stimulate ACTH and 8-endorphin secretion in vitro. These data support the hypothesis that a molecule with the same or similar structure as synthetic ovine CRP is a physiologically significant hypothalamic releasing factor.