Abstract
Antisera to purified porcine follicullar fluid inhibin of 32 K protein (pFF 32 K inhibin) were raised in rabbits.Increasing doses of an antiserum withhigh titer could neutralize the maximal suppression of FSH secretion caused by 10 ng of pFF 32 K inhibin from rat anterior pituitary cells in culture.A radioimmunoassay was developed using the antiseum and 125I-labelled pFF 32 K inhibin.Specificity of the antiserum was examined by comparing immunologicaland biological potencies of various inhibin preparations.Cross-reactivity tests revealed that the antiserum almost recognizes rat ovarian inhibinpreparations.The antiserum also recognizes purified bovine follicular fluidinhibin of 32 K protein (bFF 32 K inhibin), but with a cross-reactivity ofapproximately 20%.Cross-reactivity of human follicular fluid to the antiserumwas less than 10%.The antiserum also recognizes inhibin forms of highermolecular weights, 100 K, 80 K, and 55 K proteins, which have previously been identified by gel filtration or SDS-PAGE of crude pFF inhibin preparationsunder protein-dissociating conditions, indicating that these inhibin forms have common or closely related immunodetermining sites.
