Effect of Terminal Procedures on Liver Glycogen

Abstract

The purpose of this investigation is twofold: (a) to ascertain the effect, if any, of 2 anesthetics of the barbital series containing the cyclohexenyl group, upon the liver-glycogen content of the fasting white rat; (b) to study any possible chemotherapeutic effect that may be attributed to a methyl group linked directly to the nitrogen in one of these compounds. The 3 compounds given consideration were

(1) N-methyl 5,5′ methyl, Δ′ cyclohexenylmalonylurea—Evipal.

(2) N-desmethyl 5,5′ methyl, Δ′ cyclohexenylmalonylurea.

(3) N-desmethyl 5,5′ ethyl, Δ′ cyclohexenylmalonylurea—Phanodorn.∗

Numbers 1 and 2 are identical except for the absence of a methyl group linked to the nitrogen in the latter case; numbers 2 and 3 are identical except that in phanodorn an ethyl group replaces the methyl group. Compounds 2 and 3 are identical in hypnotic activity, furthermore compound number 2 is unstable; hence numbers 1 and 3 were chosen for investigation. 1

Male albino rats weighing between 100 and 150 gm. were fed at least 5 days on a standard diet and then fasted 48 hours before using. Those of the first group were killed by decapitation, the liver was extirpated and its glycogen content determined. The second and third groups were anesthetized with sodium evipal and sodium phanodorn respectively; the liver being removed as soon as surgical anesthesia was obtained.

Glycogen was determined by first extracting and converting to glucose, using Good's 2 modification of the Pflüger 3 method and titrating the glucose, employing the technique of Shaffer and Somogyi. 4

In order to obtain a measure of the degree of precision of the method it was applied to aliquots of fresh beef liver previously digested in 30% potassium hydroxide solution made up to a definite volume; also to the pooled livers of 5 fasted rats similarly treated. The results are recorded in Table I.