Jørgensen J C, O'Hare M M, Andersen C Y
Department of Clinical Chemistry, Rigshospitalet, University of Copenhagen, Denmark.
Endocrinology. 1990 Oct;127(4):1682-8. doi: 10.1210/endo-127-4-1682.
The present investigation provides three lines of evidence for the presence of a pro-form of neuropeptide Y (NPY) in plasma and follicular fluid. First, by the demonstration of NPY-immunoreactive material of a size corresponding to the estimated mol wt of pro-NPY. Second, an antiserum specific for the C-terminal tyrosine amide of NPY and peptide YY does not react with this material. Third, it was possible to convert the pro-NPY extracted from plasma and follicular fluid using the protease, Endoproteinase-Lys C, to a NPY-immunoreactive form eluting slightly before NPY on a G-50 column. The size of the digested product was consistent with a cleavage of pro-NPY resulting in an immunoreactive species, NPY-Gly-Lys. Pro-NPY was also found in tissue culture media from the human neuroendocrine cell line SH-SY5Y. As in the case of plasma and follicular fluid, another NPY immunoreactive species eluted from a G-50 gel filtration column slightly before synthetic human NPY. Analysis of this material with an antibody directed against the tyrosine amide of NPY in combination with isoelectric focusing revealed that this peak consisted of at least two immunoreactive forms of NPY. In conclusion, at least three different forms of NPY immunoreactivity are likely to be present in plasma, follicular fluid, and cell tissue culture media; pro-NPY, a degradation form of pro-NPY, or a biosynthetic intermediate and NPY.
本研究为血浆和卵泡液中存在神经肽Y（NPY）的前体形式提供了三条证据。第一，通过证明NPY免疫反应性物质的大小与前体NPY的估计分子量相对应。第二，针对NPY和肽YY的C末端酪氨酸酰胺的抗血清不与该物质反应。第三，使用蛋白酶内肽酶-Lys C可以将从血浆和卵泡液中提取的前体NPY转化为在G-50柱上比NPY洗脱稍早的NPY免疫反应形式。消化产物的大小与前体NPY的切割一致，产生一种免疫反应性物质NPY-Gly-Lys。在前体NPY也在人神经内分泌细胞系SH-SY5Y的组织培养基中发现。与血浆和卵泡液的情况一样，另一种NPY免疫反应性物质从G-50凝胶过滤柱上洗脱的时间比合成人NPY稍早。用针对NPY酪氨酸酰胺的抗体结合等电聚焦分析该物质，发现该峰至少由两种NPY免疫反应形式组成。总之，血浆、卵泡液和细胞组织培养基中可能至少存在三种不同形式的NPY免疫反应性；前体NPY、前体NPY的降解形式或生物合成中间体以及NPY。
