Isolation of inhibin from ovine follicular fluid using reversed-phase liquid chromatography

This report describes the application of high performance liquid chromatography (HPLC) and associated techniques to the isolation of inhibin from ovine follicular fluid (oFF). Two modes of HPLC have been assessed. High speed gel permeation chromatography on a Waters I-125 support showed that at pH 7.0 inhibin bioactivity was associated with an approx. 80000 mol. wt protein fraction which co-eluted with the bulk of the protein in oFF and gave a yield of 30-44% of the applied activity. Reversed-phase HPLC (RP-HPLC) of a peptide-rich fraction extracted from oFF was also investigated. Using analytical liquid chromatography on octadecylsilylsilica (ODS-silica), two distinct inhibin bioactive fractions were obtained, with a resultant purification of 23-fold and 3-fold respectively and an overall recovery of 8.5%. These results demonstrate that RP-HPLC may be employed as a direct and rapid technique for the isolation of inhibin from oFF.

A peptide in gastric secretion with inhibin-like properties

The presence of inhibin like peptide which is biologically active in reducing FSH secretion in castrated rats and suppressing hCG-induced increase in ovarian weights of immature mice, is reported for the first time in gastric aspirates of normal men. Immunological characteristics of this peptide were similar to inhibin extracted from human seminal plasma. The concentration of inhibin-like peptide measured by RIA developed for seminal inhibin is more than thirty-fold higher in gastric aspirates compared with serum.