High molecular weight forms of relaxin in pregnant sow ovaries

The existence of a prohormone for relaxin has been investigated by purification from extracts of pregnant sow ovaries. Radioimmunoassay of column fractions from large scale extraction of frozen pregnant sow ovaries detected two species of high molecular weight relaxin immunoactivity besides the 6,300 dalton relaxin. On further purification, these two species were resolved into three forms with apparent molecular weights of 19,000, 13,000 and 10,000 daltons respectively. Each was biologically active and could be converted by trypsin to the 6,300 dalton relaxin. They may represent intermediates of relaxin.     

Esterase and protease activity of purified guinea pig basophil granules.

Highly purified granules of circulating guinea pig basophilic leukocytes were extracted with 0.1% Triton X-100 to yield a mixture of esterases-proteases including caseinolytic activity. By selective inhibition both trypsin- and chymotrypsin-like serine hydrolases have been identified. Sigmoidal pH dependences for hydrolysis of p-tosyl-L-arginine-methyl ester and N-benzoyl-L-tryosine-ethyl ester were observed for both intact granules and Triton granule extracts. Preliminary studies indicate that the enzymes are not solubilized even after Triton X-100 treatment of the granules.