Immunoreactivity and serum destruction of N3immethyl-trh.

Pyroglu-N3immethyl-histidyl-prolineamide (MeTRH) is a more potent stimulator of thyrotropin and prolactin secretion than thyrotropin-releasing hormone (TRH). In this study, the immunoreactivity of MeTRH and its susceptibility to destruction by serum were investigated. When tested in radioimmunoassays employing four different anti-TRH sera. MeTRH had 25 to 60% of the immunoreactivity of TRH. Serum destroyed theimmunoreactivity of MeTRH at one-half of the rate at which TRH was destroyed. Slow degradation alone would not appear to explain the potency of MeTRH.