The respiratory exchange and blood sugar curves of normal and diabetic subjects after epinephrin and insulin

This communication is based on a series of experiments conducted on 5 normal men and 8 diabetics. The method of determining the respiratory exchange was carried out by the open-circuit Tissot spirometer, with gas analyses by a modified Henderson-Haldane apparatus and calculations of the indirect calorimetry by the method of Zuntz and Schumburg, as recently described by McCann and Hannon. 1 At varying intervals during the experiments samples of blood were taken and blood-sugar determinations were made according to the method of Folin and Wu. 2 Coincident pulse and blood pressure charts were also kept in most instances.

The 5 normal men showed a similar reaction to 0.5 c.c. adrenalin given subcutaneously. There was a prompt rise of the R. Q., which was most marked about 10 minutes after the adrenalin. The quotient rose to a different extent, varying with the individual. A distinct increase of heat-production occurred with its maximum degree about 30 minutes after injection, remaining above the basal figure for over an hour. There appeared an immediate and marked rise in carbohydrate metabolism with its maximum about 10 minutes after the adrenalin, as calculated from the non-protein R. Q. Coincident alveolar air analyses in one case indicated that overventilation may play a rôle in the production of the higher respiratory quotients. An elevation of blood-sugar followed the injection of adrenalin reaching a maximum in 40-50 minutes after administration. It was the most constant of any of the observed effects of the drug. The sugar remained above normal limits for over 1 1/2 hours. The pulse rate and blood pressure responded differently in different individuals.

The reaction to adrenalin of the diabetic patients differed in some respects from that in the control cases. Its appearance was the more delayed, the sicker the patient. The R. Q. did not rise nearly as high as in the controls. There was only one diab'etic patient whose R. Q. went up as many points as the minimum control. After adrenalin the eight diabetic subjects fell into two groups as regards the total heat production:—four showing an increase from 6 to 18 per cent., the rest ranging from 29 to 43 per cent. above normal. The equivalent figures for the five normal cases lay between 17 and 33 per cent. above the basal heat production. The blood-sugar did not rise as high nor as quickly as in the controls, with one exception.