Protirelin Acetate(24305-27-9 free base) (Thyroliberin Acetate) is a tripeptide that stimulates the release of thyrotropin and prolactin.

Protirelin（TRH）是一种进化古老的神经肽，在原口动物和后口动物分化之前就已存在，可能原本涉及控制胚后生长和繁殖。研究探讨了下丘脑释放激素之一的促甲状腺激素释放激素（Protirelin, TRH）对大鼠体温的影响。向体重200-250克的雄性Wistar大鼠腹腔内注射1、5、10和20 mg/kg的Protirelin。结果显示，Protirelin能够依剂量暂时性地提高体温。而在接受20 mg/kg Protirelin注射的甲状腺切除大鼠中，相较于假手术动物引发显著的高热反应，体温却未见上升。当前结果表明，甲状腺激素的释放可能参与Protirelin的高热作用。

Protirelin (TRH tartRatse) is dissolved in physiological saline (Rats).RatsNinety male Wistar rats weighing 200-250 g are subjected to the study. In the first experiment, 50 rats are divided into five groups randomly. Four doses of Protirelin dissolved in physiological saline, i. e., 1 mg/kg, 5 mg/kg, 10 mg/kg and 20 mg/kg, are administered intraperitoneally to the four groups and saline to the remaining control group. Rectal temperature is measured at the place 5 cm inner from the anus with the electronic thermister before and after treatment with Protirelin or saline. In the second experiment, 40 rats are thyroidectomized or sham-operated under the anesthesia by thiopental sodium. Ten days after the operation, 20 mg/kg of Protirelin or saline is administered to the thyroidectomized and sham-operated animals by i. p. and rectal temperature is measured using the same method as used in the first experiment. These two experiments are undertaken from 1 p, m, to 4 p. m. and the room temperature is kept at 24±1°C through the experiments including the breeding period. For a statistical analysis, Student's t test (two-tailed) is adopted.