THE EFFECT OF INTRAVENOUS ADRENALIN ON BLOOD FLOW, SUGAR RETENTION, LACTATE OUTPUT AND RESPIRATORY METABOLISM OF PERIPHERAL (LEG) TISSUES IN THE ANESTHETIZED CAT

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Abstract
At the end of 5-min. intraven. (jugular) injns. of adrenalin at rates of 0.0005, 0.001, 0.002, 0.004 and 0.008 mg./kg./min. the O2 capacity of venous blood from a hind leg, which is normally 0.14 vol. % greater than the arterial blood entering it, is still 0.10 vol. % greater; i.e., blood hy-dration is only negligibly affected. The rate of blood flow through the leg may be increased or decreased by any rate of injn. but on the avg. was increased by all, maximally by the smallest and least by the largest rate. Lactate output by the tissues of the leg was increased on the avg. by all rates of injn., maximally by the least and much less, but approx. to the same degree, by all the other rates of admn.; also maxi-mally with the greatest increases of blood flow (the 3 lowest rates of injn.) and not at all on the avg. if flowrate is decreased more than 3 ml./min. Glucose retention by the tissues of the leg was invariably increased whether flow rate was increased or decreased; maximal retention followed admn. of 0.004 mg./ kg./min., which also produced the maximal hyperglycemia. In spite of this invariable carbohydrate plethora and usual increase of lactate output, O2 utilization was not stimulated; it was actually decreased (avg.[long dash]0.17 [plus or minus]0.05 ml./min.) if blood flow was decreased; it was occasionally increased (10 of 21 instances) when flow was increased, but the avg. (+0.03 [plus or minus] 0.05) was negligible. CO2 output behaved similarly except that it increased much more (avg. +0.47 ml./min.) than O2 utilization when flow was increased, probably due to lactic acid displacement. Neither carbohydrate plethora nor increased lactate output appears, therefore, to involve an increase in respiratory metabolism of the leg tissues; and adrenalin augmentation of metabolism for the animal as a whole (calori-genic action) only occasionally receives augmentation from these peripheral tissues and must usually occurs despite them.