Chromatographic studies with pig adrenocorticotrophin

Abstract

Carboxymethylcellulose has been used to prepare corticotropin A1 and show that at least 3 other chromatographically distinct cortico-tropins are present in oxycellulose concentrates. One of these has been identified with corticotropin A2 and the other 2 have been named cortico-tropins A1a and A1b. In agreement with previous workers alkali has been shown to convert corticotropin A1 into A2, and corticotropins A1a and A1b into less-retarded substances on carboxymethylcellulose columns. One of these products has been tentatively identified with corticotropin A3. Diethylaminoethylcellulose has been used to fractionate oxycellulose concentrates, although large losses in biological activity were observed. Corticotropin A1 behaved as a homogeneous substance on diethylaminoethylcellulose, and oxidized A1 and A1 were partially separated.