A STUDY OF THE EFFECTS OF MORPHINE AND OF CARBON TETRACHLORIDE ON THE RATE OF DISAPPEARANCE OF ETHYL ISOAMYL BARBITURIC ACID

¹ From the Department of Pharmacology and Toxicology, University of Wisconsin, Madison

The rate of disappearance of amytal from the tissues was studied in (a) normal rabbits, (b) rabbits premedicated with morphine, and (c) rabbits premedicated with CCl₄. Observations were made on the rate of disappearance of bromsulphalein from the blood stream on a similar series of rabbits.

The increase in duration of anesthesia produced by the combination of morphine or CCl₄ with amytal is closely correlated with the effects which these drugs have on the retention of bromsulphalein in the blood stream. The duration of anesthesia in the three series of animals parallels the rate of disappearance of the amytal from the blood stream. The animals of each series regain their righting reflexes when the concentration of the amytal in the blood reaches approximately the same level, viz, 2.9 mgm. per cent. Morphine decreases the rate of disappearance of the barbiturate at least in part by altering the blood supply to the liver, while the primary effect of CCl₄ appears to be the production of liver injury.