Alteration by prolonged oral administration of a thyrotropin-releasing hormone analog, TA-0910, of the pituitary-thyroid axis in subjects with brain stroke.

We evaluated whether prolonged oral administration of a novel analog of thyrotropin-releasing hormone (TRH), TA-0910, may change the pituitary-thyroid axis in human subjects with brain stroke. The subjects were given one oral dose of 2.5-20 mg of TA-0910 daily for 8 weeks, and then blood levels of TA-0910, thyroid hormones and thyrotropin (TSH) were measured. Plasma levels of TA-0910 were elevated with increasing doses. After administration of TA-0910, the basal levels of thyroid hormones and TSH had a tendency to increase and decrease, respectively, but those changes remained in the normal range. The secretion of TSH in response to TRH was not significantly affected by TA-0910 administration. No significant changes in other pituitary hormones were observed after TA-0910 administration. The present data indicate that prolonged oral administration of TA-0910 did not significantly alter the pituitary-thyroid axis in subjects with brain stroke.