Melanin Concentrating Hormone (MCH), a 19 amino acid cyclic peptide, is largely expressed in the hypothalamus. Melanin Concentrating Hormone is implicated in the control of general arousal and goal-orientated behaviours in mammals, and appears to be a key messenger in the regulation of food intake.

α-Neo-Endorphin (1-7)

RLX-33 是一种有效且具有选择性和血脑屏障透过性的松弛素家族肽 3 (RXFP3) 拮抗剂，也阻断松弛素 3 (relaxin 3) 诱导的 ERK1/2 磷酸化，对 RXFP3、以及 ERK1 和 ERK2 磷酸化的 IC50 分别为 2.36 μM、7.82 μM 和 13.86 μM。RLX-33 能阻断 RXFP3 选择性激动剂 R3/I5 诱导的大鼠食物摄取增加。RLX-33 可用于代谢综合征的研究。