Protirelin (Thyroliberin) is a tripeptide that stimulates the release of thyrotropin and prolactin.

THR:

Protirelin (TRH), a neuropeptide predating the split between protostomes and deuterostomes, has likely played a role in regulating postembryonic growth and reproduction from its evolutionary origins. This study explores Protirelin's impact on body temperature, specifically through the administration of 1, 5, 10, and 20 mg/kg doses intraperitoneally to male Wistar rats (200-250 g). The findings reveal that Protirelin induces a temporary, dose-dependent increase in body temperature. Notably, thyroidectomized rats receiving a 20 mg/kg dose of Protirelin do not exhibit the significant hyperthermia observed in sham-operated counterparts, indicating that thyroid hormone release may be essential to Protirelin's hyperthermic effect.

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.