Buffer Influence Upon Response of Striated Muscle to Caffeine Stimulation in Fatigue Studies

Abstract

Summary1. The characteristic positive effect of caffeine in delaying the rapidity of fatigue in the gastrocnemius muscle is apparent when administered in an aqueous medium, or in a bicarbnate buffered-Ringer medium. 2. The effect of the medium containing the caffeine is greater than the effect of the medium alone. 3. A reversal of the usual caffeine effect upon the fatigue record of striated muscle occurs when the caffeine is introduced in a phosphate bufferetl medium, or in a phosphate buffered-Ringer medium. 4. Both phosphate-buffered caffeine solutions cause a negative effect to that of the medium alone. 5. The necessity of discretion in the choice of a buffer in the maintenance of the desired pH of a solvent medium is evident; and, the elimination of an aqueous or Ringer phosphate buffered solution as a solvent for caffeine, in studies of the effect of caffeine upon the fatigue record of the striated (gastrocnemius) muscle. is indicated specifically.