Cross-talk of second messengers during the systemic trauma response following burn injury: how, when, and where.

The systemic effects of trauma from large body surface area (% BSA) burns were evaluated in terms of second messenger levels involving polyinositol phosphates as they related to adenosine 3':5'-cyclic monophosphate (cAMP), myoplasmic Ca2+, and active tension. Gastrocnemius muscles were harvested after muscle twitch at postburn day 21. Levels of polyinositols were measured by incorporation of myo-[2-3H]-inositol, with separation of the phosphates by anion-exchange chromatography. Analysis of variance was used for statistical evaluation. Multivariate relationships between the: 1) independent polyinositol forms (3H-inositol, I1P, and I1,4,P2) and dependent I1,4,5,P3 existed for control (R2 = 0.71) and 20% BSA burn (R2 = 0.67) groups; 2) the independent polyinositol forms (I1P, I1,4,P2, and I1,4,5,P3) and dependent cAMP for control (R2 = 0.73), 20% BSA (R2 = 0.99), and 50% BSA (R2 = 0.99) groups; 3) independent polyinositol forms (I1P, I1,4,P2, and I1,4,5,P3) and dependent 45Ca2+ for the control (R2 = 0.99), 20% BSA (R2 = 0.44), and 50% BSA (R2 = 0.82) groups; and 4) independent polyinositol forms (I1P, I1,4,P2, and I1,4,5,P3) and dependent active tension for 20% BSA (R2 = 0.97) and 50% BSA (R2 = 0.64) burn groups. Numerous interrelationships existed with each of the multivariate tests. These analyses confirm that several independent polyinositols contribute to changes in the second messengers of I1,4,5,P3, cAMP, and Ca2+ in skeletal muscle as a result of the systemic trauma of burn injury.