Changes of immunoreactive TRH in cerebrospinal fluid and plasma after acute head injury and its clinical significance.

Using radioimmunoassay (RIA) concentrations of immunoreactive TRH (TRH-ir) in cerebrospinal fluid (CSF) and plasma were determined after acute head injury in 29 patients. The results showed that the concentrations of TRH-ir (pmol/L) in CSF and plasma on the days when injuries were sustained were 29.25 +/- 8.92 pg/ml and 30.29 +/- 8.26 (1 pg/ml = 2.8 pmol/L) in mildly (n = 12), 57.78 +/- 11.72 and 65.27 +/- 8.57 in moderately (n = 9), and 70.09 +/- 7.58 and 85.65 +/- 7.92 in severely (n = 8), head-injured patients. While the concentrations of TRH-ir in CSF and plasma were 25.11 +/- 11.85 and 27.90 +/- 11.39 in the control group (n = 10). Dynamic observations revealed that the contents of TRH-ir in CSF and plasma were gradually recovered to their control levels when improvement of the head-injured patients took place. But they were significantly decreased and became much lower than the control levels in patients with poor prognosis. These results suggest that the assay of TRH-ir in CSF and plasma has clinical significance in reflecting the severity and prognosis of acute head-injured patients.