gamma-Butyrobetaine as a specific antagonist for carnitine in the development of the early chick embryo.

The effect of gamma-butyrobetaine alone and with the addition of carnitine on the development of the early excised chick embryo has been studied. gamma-Butyrobetaine in appropriate amounts exerts an inhibitory effect which can be relieved or annulled by the inclusion of appropriate amounts of carnitine. This has been interpreted as a metabolite-antimetabolite relationship, in which the normal metabolite, carnitine, is antagonized by the structurally closely related gamma-butyrobetaine, and is regarded as evidence of an important role of carnitine in the metabolism of the developing chick embryo.