Earl R. Norris

Cell proliferation accelerating and inhibiting substances in normal and cancer blood and urine.

Conclusions 1. Blood serum and urine contain two types of substances; the one which accelerates the rate of cell prolifera- tion, and the other which inhibits the rate of cell proliferation. 2. Normal blood sera and normal and pathological urine accelerate the rate of cell proliferation in bone marrow cultures in vitro because of an excess of accelerating substances over inhibiting substances present. 3. Blood sera from neoplastic disease, pernicious anemia and leukemia inhibit cell proliferation in bone marrow cultures because of an excess of inhibiting substances over accelerating substances present. 4. Individual urine and blood serum specimens have been shown by adsorption on Norit and elution with NaOH and ammoniacal acetone to have both inhibiting and accelerating substances present.

Effect of Some Capillary Active Substances on the Permeability of Collodion Membranes.

Brinkman and Szent-Györgyi 1 report that various capillary active substances, alkaloids 2 and purine bases (sodium oleate, sodium linoleate, sodium glycocholate, digitonin, Wittes peptone, atropine, pilocarpine, caffeine, strychnine, quinine and morphine) cause permeability of collodion membranes to hemoglobin. Rosenthal 3 states that sodium taurocholate possesses the property of increasing the degree of permeability of semi-permeable collodion membranes to dyestuffs. Clausen has shown the presence of some capillary active substance in blood serum 4 and urine of patients suffering from parenchymatous nephritis (nephrosis) which greatly lowers the surface tension, and reports that the addition of blood serum, urine, or, a water solution of the alcohol soluble portion of the colloidal residue from evaporated urine of these patients, will cause collodion membrane to become permeable to proteins. 5 Grollman 6 finds that the collodion sacs used in his investigation were not rendered permeable to hemoglobin by use of bile salts, sodium oleate, lanthanum chloride, acid or alkali. The permeability of collodion membranes may be varied by many factors in their preparation and subsequent treatment. It has been shown to depend upon the thickness and the ratio of wet to dry weight of the finished membrane, or, according to Brown, 7 upon the alcoholic index of the membrane. Membranes were prepared in 2 × 17 cm. test-tubes, using 5 cc. of a solution of 2 gr. nitro cellulose in 100 cc. of alcohol-ether mixture. After drying, the membranes were graded according to the method of Brown. Solutions of various substances were placed in the membranes and the membranes then placed in distilled water, the rate of diffusion of the substance across the membrane king taken as an index of the permeability of the membrane, when calculated as the ratio of the concentration outside divided by the concentration inside the membrane at various times.

Cell Proliferation Accelerating and Inhibiting Substances in Blood Serum During Pregnancy.

Summary 1. Two types of factors which affect cell proliferation have been observed in blood serum, one of which accelerates the rate of normal cell proliferation, and the other inhibits the proliferation of normal cells. Normal blood serum contains a predominance of factcrs which accelerate the rate of normal cell proliferation. During pregnancy there is a progressive change in the balance of factors which affect cell proliferation such that the factors which inhibit proliferation of normal cells become predominant. 2. The rate of cell proliferation of a cell suspension in vitro of cells obtained from rat embryos and fetuses, at least up to the 15th day of pregnancy, is accelerated by 2-amino-4-hydroxy-7-methyl pteridine and cancer blood serum and inhibited by xanthopterin and normal human blood serum. 3. The rate of cell proliferation of a cell suspension in vitro, of cells obtained from rat young at the time of birth, is accelerated by xanthopterin and normal human blood serum and inhibited by 2-amino-4-hydroxy-7-methyl pteridine and cancer blood serum.