Experimental Study of Dibutyryl Cyclic AMP: Its Antishock Effects Observed in Traumatic Shock Rats

Abstract

Antishock effect of N⁶, O₂-dibutyryl cyclic AMP (DBcAMP) was investigated in rats subjected to Noble-Collip drum trauma and compared with effects of hydrocortisone and Trasylol. Results obtained are as follows. 1) Hydrocortisone and Trasylol administered 1 hr before initiating drumming improved the survival rate from traumatic shock with concomitant reducton of levels of acid phosphatase and β-glucuronidase in circulating blood. DBcAMP administered i. p. immediately after trauma also improved the survival rate to the same extent as did Traylol or hydrocortisone, while no inhibitory effects were observed on acid phosphatase and β-glucuronidase. 2) The rectal temperature fell significantly after suffering trauma, and the rats with greater fall in rectal temperature had poorer chance for survival. The fall in rectal temperature was considerably prevented by DBcAMP in a dose of 0.5 mg/100 g body weight (b. w.). 3) DBcAMP induced a rise in plasma insulin level (IRI) and insulin/glucose ratio (I/G) in shock rats, and the elevation in blood lactate/ pyruvate ratio (L/P) and excess lactate otherwise observed after trauma were satisfactorily prevented by DBcAMP administration. It is concluded that the antishock effects of DECAMP primarily resulted from improvements of the intracellular metabolism induced by its easy passage through the cell membrane and its cAMP like action, while any preventive action was not observed against elevation of lysosomal enzymes in the circulating blood.