Increased urinary levels of thyrotropin-releasing hormone immunoreactivity in acute pancreatitis

Thyrotropin-releasing hormone (TRH) has been shown to be present and have actions in the human gastrointestinal tract. We have studied urine TRH immunoreactivity (TRH-ir) levels in healthy subjects and patients with acute pancreatitis, gallstones, ulcerative colitis, or acute gastritis. The urine samples were prepurified by SP-Sephadex-C-25 cation exchange chromatography, subjected to reverse-phase high-pressure liquid chromatography, and assayed in our TRH radioimmunoassay. The mean urine TRH immunoreactivity values of healthy subjects were 4.42 +/- 1 ng/l (x +/- SEM); of patients with acute pancreatitis on the 1st day of hospitalization, 23 +/- 7 ng/l; on the 2nd day, 7 +/- 1 ng/l; and on the 3rd day 9 +/- 2 ng/l. Only the urine TRH levels of the pancreatitis patients on day 1 differed significantly (p less than 0.05) from the levels of the healthy subjects. Circulating TRH appears to be derived mostly from the pancreas, where the islets during acute pancreatitis are affected, and TRH is released into circulation and urine.