Ohmori M, Endo T, Ikeda M, Onaya T
Third Department of Internal Medicine, University of Yamanashi Medical School, Japan.
Biochem Biophys Res Commun. 1991 Jul 31;178(2):733-8. doi: 10.1016/0006-291x(91)90169-8.
To identify the site(s) on the thyrotropin (TSH) receptor that interacts with TSH or thyroid stimulating antibody (TSAb), we examined the effect of the synthetic TSH receptor peptide (termed N2 peptide, No. 35-50) on the cAMP accumulation induced by TSH or TSAb. Preincubation of bovine TSH with N2 peptide resulted in a significant and dose-dependent decrease in cAMP accumulation. This decrease was not observed when bovine TSH was preincubated with P1 peptide, which was used as a control (No. 398-417). In contrast, the N2 peptide did not affect TSAb activity in immunoglobulin fractions from three TSAb-positive patients with Graves' disease. P1 peptide also had no effect on TSAb activity. These results suggest that the N-terminal region of the TSH receptor is important for TSH action, and also that TSAb activity cannot be suppressed only by the application of the synthetic peptide corresponding to the N-terminal region.
为了确定促甲状腺激素（TSH）受体上与TSH或甲状腺刺激抗体（TSAb）相互作用的位点，我们研究了合成的TSH受体肽（称为N2肽，第35 - 50位）对TSH或TSAb诱导的环磷酸腺苷（cAMP）积累的影响。牛TSH与N2肽预孵育导致cAMP积累显著且呈剂量依赖性降低。当牛TSH与用作对照的P1肽（第398 - 417位）预孵育时，未观察到这种降低。相反，N2肽对来自三名格雷夫斯病TSAb阳性患者的免疫球蛋白组分中的TSAb活性没有影响。P1肽对TSAb活性也没有影响。这些结果表明，TSH受体的N端区域对TSH作用很重要，并且TSAb活性不能仅通过应用对应于N端区域的合成肽来抑制。
