ARG-PRO-GLY-PRO-PRO-GLY-LEU-GLN-GLY-ARG-LEU-GLN-ARG-LEU-LEU-GLN-ALA-ASN-GLY-ASN-HIS-ALA-ALA-GLY-ILE-LEU-THR-MET-NH2;HYPOCRETIN-B, MOUSE;H-ARG-PRO-GLY-PRO-PRO-GLY-LEU-GLN-GLY-ARG-LEU-GLN-ARG-LEU-LEU-GLN-ALA-ASN-GLY-ASN-HIS-ALA-ALA-GLY-ILE-LEU-THR-MET-NH2;OREXIN B (MOUSE);OREXIN B (MOUSE, RAT);OREXIN B (RAT, MOUSE);OREXINS OREXIN B RAT, MOUSE;RPGPPGLQGRLQRLLQANGNHAAGILTM-NH2
Human Orexin B significantly augments food intake; at the 2 hr time point, 5- and 12-fold stimulation of food consumption is observed by 3 nM and 30 nM orexin-B, respectively.
体外研究
Orexin B is derived by proteolytic amino acid precursor, prepro-orexin, which is encoded by a gene localized to chromosome 17q21 in humans. In radioligand binding studies, Orexin B has a higher affinity for the OX2 receptor. Human Orexin B has two amino acid substitutions when compared with the rodent sequence. OX2 receptor is indeed a high-affinity receptor for human orexin B, with an IC
50
of 36 nM in the binding assay and an EC
50
of 60 nM in the [Ca
2+
]i transient assay. Human Orexin B has significantly lower affinity for the human OX1: the calculated IC
50
in the competitive binding assay and the EC
50
in the [Ca
2+
]i transient assay are 420 nM and 2500 nM for human orexin-B, respectively.
生物活性
Orexin B, rat, mouse 是 Orexin 受体的内源性激动剂,与 OX1 和 OX2 结合的 Ki 值分别为420和36 nM。