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In this paper we are reporting the results of a study of the distribution of ascorbic acid in the blood in human subjects and in guinea pigs. EXPERIMENTALFifty healthy medical students (47 males and 3 females) on self-selected diets and 50 patients (41 males and 9 fe-. males) in a municipal hospital were studied. Oxalated blood samples were collected under fasting conditions about 15 hours post-prandial. The ascorbic acid con-,.tent of the whole blood and the plasma was determined by the method of Roe and Kuether (1). The concentration of ascorbic acid in oxalated whole blood and plasma was also determined by the same method in guinea pigs upon an apparently adequate diet (2) made up to contain different levels of ascorbic acid. RESULTS

diabetic rats showed good reductions in glucose-6^phosphatase activity. The rise in glucose-6-phosphatase activity after alloxan, previously reported by other groups, 6 ' 7 was observed also. The results of this experiment indicate that insulin is required for the effect of BZ-55 on the glucose-6-phosphatase activity of liver, but whether or not an increased amount of insulin is necessary for this effect is not known at present.Another effect of BZ-55 which has been noted previously is its influence on the thyroid. The administration of BZ-55 w a s observed to cause a reduction in I 131 uptake by the thyroid gland and, over a period of time, an increase in its size. Dr. J. Logothetopoulos has compared BZ-55 afl d Orinase with respect to I 131 uptake and goitrogenic effect. He found the reduction in I 131 uptake to be much more pronounced in rats treated with BZ-55 t n a n m those treated with equimolecular quantities of Orinase. The goitrogenic effect of BZ-55 w a s m S n also, whereas Orinase in similar doses did not have a goitrogenic effect. In his series too, the hypoglycemic effects of these materials appeared to be unrelated to their effect on the thyroid gland.It is difficult to interpret the various results. We can say, however, that the results presented seem to be •consonant with a stimulation of insulin secretion by BZ-55. It 1S evident too that the presence of insulin is required for at least one of the changes in the activity of the liver, namely the effect on glucose-6phosphatase. However, the fact that BZ-55 does not appear to stimulate glucose uptake or glycogen formation in muscle is against this view unless this drug, in addition to stimulating insulin secretion, also has an effect which masks the action of insulin on muscle. REFERENCES 1 BZ-55 (carbutamide): Experimental and clinical studies of an oral antidiabetic agent. Canad. M. A. J. 74:957-98, 1956. 2 Ashworth, M. A., and Haist, R. E.: Some effects of BZ-55 (carbutamide) on the growth of the islets of Langerhans. Canad. M. A. J. 74:975-76, 1956. 3 Friedlich, T. L., Ashworth, M. A., Hawkins, R. D., and Haist, R. E.: An effect of BZ-55 (carbutamide) on the rate of absorption of glucose from the gastrointestinal tract. Canad. M. A. J. 74:973-74, 1956. 4 Kleibel, F.: Chemical structure of sulphonamides and their effect on peristalsis. Lancet 1:882-83, 1954. 5 Ashmore, J., Hastings, A. B., Nesbett, F. B., and Renold, A. E.: Studies on carbohydrate metabolism in rat liver slices. VI. Hormonal factors influencing glucose-6-phosphatase. J. Biol. Chem. 218:77-87, 1956. 6 Ashmore, J., Hastings, A. B., and Nesbett, F. B.: The effect of diabetes and fasting on liver glucose-6-phosphatase. Proc. Nat. Acad. Sci. 40:673, 1954. 7 Langdon, R. G., and Weakley, D..R.: The influence of hormonal factors and of diet upon hepatic glucQse-6-phosphatase activity.In a previous publication 1 it was shown that addition of carbutamide (Amino-phenurobutan, Lilly) to a rat liver microsome preparation in vitro had no significant effect on the glucose-6-phosphatase activi...