Poon A M, Pang S F
Department of Physiology, University of Hong Kong.
Neurosci Lett. 1994 May 23;173(1-2):167-71. doi: 10.1016/0304-3940(94)90175-9.
Effects of 10 and 50 mumol/l guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S) on 2-[125I]iodomelatonin binding in the chicken bursa of Fabricius and spleen were tested. In the chicken bursa of Fabricius, GTP gamma S increased the Kd of 2-[125I]iodomelatonin binding sites without affecting the Bmax value. In contrast, GTP gamma S caused both an increase in Kd and a reduction in Bmax of 2-[125I]iodomelatonin binding sites in the chicken spleen. Our results suggest the existence of subtypes of melatonin receptors with different receptor-G protein-effector complexes in the avian primary and secondary lymphoid systems.
测试了10和50微摩尔/升的鸟苷5'-O-(3-硫代三磷酸)(GTPγS)对鸡法氏囊和脾脏中2-[125I]碘褪黑素结合的影响。在鸡法氏囊中，GTPγS增加了2-[125I]碘褪黑素结合位点的解离常数(Kd)，而不影响最大结合容量(Bmax)值。相反，GTPγS导致鸡脾脏中2-[125I]碘褪黑素结合位点的Kd增加和Bmax降低。我们的结果表明，在禽类的初级和次级淋巴系统中存在具有不同受体-G蛋白-效应器复合物的褪黑素受体亚型。
