| Abstrakt: |
1A study of the relation of the blood concentration of ascorbic acid to the tissue concentrations and to the histology of the teeth has been made in the guinea pig.2The most efficient rate of withdrawal of ascorbic acid from the blood by liver, spleen, kidney, adrenal gland, brain, skeletal muscle and cardiac muscle occurs at a whole blood concentration of this vitamin near 0.25 mg. per 100 ml.3A concentration of ascorbic acid in the tissues reflected by a blood level above 0.22 mg. per 100 ml. of whole blood will prevent the appearance of any pathological lesions in the incisor teeth of the guinea pig.4The most obvious pathological changes due to ascorbic acid deficiency are to be found in the odontoblastic layer.5An alteration in the calcification pattern of the incisor teeth occurs at about the same blood levels as those associated with beginning changes in the odontoblastic layer, but the former changes are not as consistent or as easily interpreted.6Conventional methods of determining the presence of scurvy, such as the appearance of hemorrhages, reduced growth rate, or loosening of the teeth, are too inaccurate and insensitive to be of any value in detecting a mild ascorbic acid deficiency in the guinea pig.7An intake of 1.23 mg. of ascorbic acid per 100 gm. of body weight is required in the guinea pig to produce a whole blood level of 0.25 mg. per 100 ml. Translated to man, this requirement would be equivalent to an intake of 861 mg. per day on a basis of body weight or 196 mg. per day on a surface area basis. These data indicate that the vitamin C requirement of the guinea pig is higher than that of man.8Since there has been observed in the guinea pig a definite relation between the concentration of ascorbic acid in the tissues and that in the blood, it is suggested that the determination of the ascorbic acid content of the whole blood is the best procedure for evaluating the nutritional status of an animal with respect to vitamin C. |
