an experiment was performed on 21-day-old male rats to determine the combined effects of pinealectomy , constant light and darkness , and intraperitoneal ( i.p . ) thyrotropin-releasing hormone ( trh ) on pituitary and plasma radioimmunoassayable thyrotropin ( tsh ) , serum thyroxine ( t4 ) , and pituitary , thyroid and body weights at the age of 25 days .
C0040162
thyrotropin-releasing hormone
C0032002
pituitary