Sullivan K A, Shiao L L, Cascieri M A
Department of Molecular Pharmacology and Biochemistry, Merck Research Laboratories, Rahway, New Jersey 07065-0900, USA.
Biochem Biophys Res Commun. 1997 Apr 28;233(3):823-8. doi: 10.1006/bbrc.1997.6542.
The diverse biological functions of galanin are mediated via membrane bound high-affinity receptors. In order to identify and characterize potential galanin receptor subtypes, we have examined the specific 125I-galanin binding to the CHP-212 human neuroblastoma cell line. The galanin receptors expressed in CHP-212 cells, like GALR1 have high affinity for galanin (Kd = 0.07 nM) and the potency for inhibition of 125I-galanin binding by galanin peptides parallels that of hGALR1 expressed in a stable CHO cell line. We confirmed that GALR1 is expressed in these cells by RT-PCR. We further determined the tissue expression patterns of hGALR1 which is expressed in a variety of human tissues at a very low level, with the highest levels seen in heart, small intestine and prostate. A species of approximately 70 kDa is recognized by antisera specific for hGALR1 by Western blot analysis and should allow future measurements of receptor protein expression.
甘丙肽的多种生物学功能是通过膜结合的高亲和力受体介导的。为了鉴定和表征潜在的甘丙肽受体亚型，我们检测了125I-甘丙肽与CHP-212人神经母细胞瘤细胞系的特异性结合。CHP-212细胞中表达的甘丙肽受体，与GALR1一样，对甘丙肽具有高亲和力（Kd = 0.07 nM），甘丙肽肽抑制125I-甘丙肽结合的效力与稳定CHO细胞系中表达的hGALR1相当。我们通过RT-PCR证实了这些细胞中表达了GALR1。我们进一步确定了hGALR1的组织表达模式，其在多种人体组织中以非常低的水平表达，在心脏、小肠和前列腺中表达水平最高。通过蛋白质印迹分析，抗hGALR1的抗血清识别出一种约70 kDa的蛋白，这将有助于未来对受体蛋白表达的检测。
