In dogs immediately after the shock induced by Witte peptone 300mg/kg or by bovine serum anaphylaxis, the presence of adenine nucleotides or 5-hydroxytryptamine in the blood plasma obtained from the femoral and hepatic veins were examined. But our present methods of spectrophotometry of the deproteinized plasma or paper chromtography of the deproteinized, freeze-dried plasma failed to reveal any increase in either substance of these.