Intercellular hormones

Abstract

Assays of the content of the vit. B complex factors in suspension fluids from u.-v. damaged cells (I) and from undamaged cells (II) showed I to contain greater amts. of biotin, folic acid, inositol, nicotinic acid, pantothenic acid, pyridoxin, riboflavin and aneurin, the maximum ratio being 91.5 X for pantothenic acid, the minimum 2.3 X for inositol. A soln. of factors of the B complex corresponding to the quantities found in I stimulated the growth of yeast more than did those of II, the relative proliferation-promoting potencies being 25.9 and 4.5. Factors of the vit. B complex account for part but not all of the proliferation-promoting effect of products from damaged yeast cells. Samples of the intercellular fluids, cell-residue wash waters, and residue autolysates from damaged cells had a greater proliferation-promoting effect on yeast than those from undamaged cells. Certain proliferation-promoting factors are replaced within the damaged cells as they are lost to the intercellular fluids by diffusion following cell damage. Instances in which lesser yields were obtained may possibly be explained by photochemical destruction in the irradiated prepns.