Instability of Metabolic Quotients Obtained from Tissue Cultures.

Abstract

Maximal growth of Earle''s Strain L cells is obtained by using 15-20% horse serum with a medium containing 0.5% lactalbumin hydro-lysate. Rate of lactate formation decreases as pH decreases but remains constant if the suspension is adequately buffered with bicarbonate. Respiration continues as a straight line function with time even though pH decreases. Sera from different horses affects growth rate of tissue cultures differently. Young, rapidly growing tissue cultured cell strains respire and glycolyze at a greater rate than old ones. Metabolic rate is related to growth rate. Metabolic quotients obtained on tissue cultures grown in serum, have little quantitative significance when considered alone, because serum is not chemically definable.