[Hypothalamic-adenohypophysial function of corticotropin releasing hormone (CRH)-ACTH system in brain death].

To evaluate the hypothalamic-adenohypophysial function of corticotropin releasing hormone (CRH)-ACTH system in brain death, basal serum values of ACTH and cortisol was measured, and in addition, insulin-tolerance test (ITT) and CRH stimulation test was performed is 28 brain death cases. Basal levels of ACTH were low-normal, whereas those of cortisol were high-normal, and no correlation was observed between them. There was no correlation between these levels and the age, sex, cause of the brain death, and the incidence of hypotention. However, basal ACTH value significantly decreased within a few days (p < 0.01), and ACTH was undetectable in all cases 5 days after the diagnosis of the brain death. On the other hand, ITT and CRH test was negative in all cases. These results suggest that some degree of adenohypophysial function of ACTH secretion remains for a few days after the diagnosis of the brain death. Compared with other adenohypophysial hormones of the brain death cases in previous reports, however, ACTH was lower, decreased more rapidly, and did not response to the direct pituitary stimulation test, the CRH test. These results further suggest that disturbance of ACTH secretion occurs from an early stage in the brain death cases.