Induction of plasma protein synthesis in response to trauma

Abstract

A characteristic response to injury is a transient reduction in serum albumin and an increased hepatic synthesis of certain [alpha]-globulins (seromucoid fraction). A 5-fold increase in glycine-C-14 incorporation into the seromucoid fraction of rat plasma was observed 24 hr. after laparotomy. This response to trauma was abolished by injections of either puromycin or actinomycin D. Puromycin also inhibited the incorporation of labeled glycine into albumin whereas actinomycin D did not. These results were interpreted to mean that the response to trauma involved an increased transcriptive process at the DNA-RNA [deoxyribonucleic acid-ribonucleic acid] level followed by a de novo synthesis of seromucoid proteins. When the actinomycin D was administered at[long dash]2, 0, and +2 hr. relative to the time of injury, the 24-hr. response was abolished, whereas at +4 hr. a definite increase in seromucoid synthesis was observed. These results were interpreted to mean that messenger RNA was formed between the 2nd and 4th hr. after injury. It is proposed that the elevation in the seronucoid fraction in response to injury is an inductive process involving an increased production of messenger RNA. Albumin synthesis, which was not significantly changed, may be under separate control and is not inducible by trauma.