Stimulation of Gluconeogenesis in Rat Liver Slices by Epinephrine and Glucocorticoids

Abstract

L-Epinephrine, in concentrations of 10^–7M or greater, stimulated gluconeogenesis in rat liver slices prepared from adrenalectomized animals and incubated with L-alanine as substrate. This response was rapid in contrast to the stimulation by glucocorticoids that was characterized by a lag period of about 1 hr. Levels of intermediate compounds within the epinephrinetreated tissue were changed in a pattern similar to that seen with triamcinolone treatment:pyruvate concentration was decreased, and malate and phosphoenolpyruvate concentrations were raised. Other similarities between the 2 responses were that both hormones stimulated urea formation and both increased incorporation of ¹⁴C from alanine-U-¹⁴C into glucose. The responses differed in that triamcinolone decreased ketone body formation whereas epinephrine did not affect it; epinephrine elevated the level of acetylcoenzyme A within the tissue; triamcinolone did not. Triamcinolone did not affect the level of adenosine 3′,5′-monophosphate; epinephrine had elevated it slightly at the time measurements were made. (Endocrinology84: 622, 1969)