Mucoproteins of Human Plasma. III. Electrophoretic Studies of Mucoproteins from Perchloric Acid Filtrates of Plasma.

Abstract

animals the full supplement a t a time most conducive to overcoming the acute phase of the deficiency.The present data indicate that vit. B12 is about equally effective by oral or injection administration in promoting growth of young rats on highly specialized depletion diets. The deficiency of vit. Bl2 induced in rats by these rather extreme dietary means does not, therefore, appear to evoke a failure in utilization of the vitamin, but rather a true deficiency and enhanced need for the vitamin itself.The following additions to the diet failed to yield a comparable growth response, and even appeared /to have an inhibitory effect: 510% purified casein, 5-10% of various primary-grown and brewer's yeasts, and additional folic acid. The addition of thymidine, 25-50 mg per kg diet, 4betaine hydrochloride 0.5%) or additional choline 0.1% likewise did not stimulate growth in absence of vit. B12.The growth promoting action of vit. BIZ in rations containing iodinated protein has recently been reviewed.1° Betheil and Lardyll have further compared the effectiveness of vit. BIZ, whole liver substance and extracts high in APA activity, as growth promoting materials for hyperthyroid rats. The ration used by tthese authors was also based on puri-1Q Nutrition Reuiews, 1949, 7: 183. 11 Betheil, J. J., and Lardy, H. A., J . 3--utvition, c 1949, 37, 495.fied casein, 'but did not contain a sulfa drug. I t is worthy of note that mortality is high among our control animals and that death is generalIy preceded by appearance of hemorrhage about the nose and paws. Vit. B12 clearly prevents this syndrome and has a marked effect toward longevity under the dietary conditions imposed.The question of the equivalence of vit. B12 with U.S.P. anti-pernicious anemia units can only be answered by assays in human pernicious anemia patients. Microbiological and animal assays may serve as a useful guide, however, toward this goal. The data presented provide some evidence that concentrated liver extracts which show a. correlation by microbiological assay of 1 U.S.P. unit approximately equal to 1 pg of vit. B12, show a similar approximate equivalence by rat assay. Summary. The growth response of vit. BIZ 'depleted rats under the conditions studied is proportional to the vit. B12 administered in the critical range of .025-.1 pg per rat day. Oral and injection administration of the vitamin at critical levels yield approximately equal growth responses. Addition of the vitamin to the diet, multiple dosing or single dosing the first day of assay also appear roughly equivalent. A preliminary correlation between the results of microbiological and rat assays as applied to injectable liver extracts was obtained.

Effect of Acute Clinical Stress on the Levels of Hexosamine in Serum and Its Excretion in Urine

“…In one instance (case of gout) the increase in serum hexosamine was found to be in the hexosamines contained in the alpha-globulin fractions. This is consistent with observations that the alphaglobulins (12) and hexosamine-rich alpha-globulin mucoproteins (13,14) increase in response to other acute injuries or diseases such as burns (12) and pneumonia (13,14).…”

Total Nondialyzable Solids (Tnds) in Human Urine. Iv. Electrophoretic Properties of Rs-1 Subfraction*

“…is.d. Gradient 3 of RS-1 had a mobility consistent with isolated serum MP-2, which Mehl and coworkers reported as -2.4 to -2.8 x 1O5 (7). This gradient appeared unchanged in fraction RS-1B as gradient 1.…”

“…Alpha-2 mucoproteins include at least three electrophoretically homogenous components, all with isoelectric points of 3.7 to 4.4 (7,17). Haptoglobulin has an electrophoretic mobility similar to the alpha-2 globulins and has been recovered from human serum and nephrotic urine (14).…”

Electrophoretic Studies of the Vitamin B12-Binding Protein of Normal and Chronic Myelogenous Leukemia Serum*

“…The vitamin B12 of normal and CML serum moves with the a-globulins when serum is electrophoresed at pH 8.6 (1,8,9). The seromucoid, the fraction of serum containing glycoproteins which comprises about 1.5 per cent of the serum proteins (10), moves with the a-globulins when electrophoresed at pH 8.6 (11). Furthermore, it has been found that the seromucoid fraction isolated from CML serum is capable of binding amounts of added cobaltOO-labeled vitamin B12 (B,2*) sufficient to account for the increased binding capacity of the whole serum (12).…”