dc.contributor.author | Kaneko, Nobuto | |
dc.contributor.author | Nilsen, Tom Ole | |
dc.contributor.author | Tanaka, Hanae | |
dc.contributor.author | Hara, Akihiko | |
dc.contributor.author | Shimizu, Munetaka | |
dc.date.accessioned | 2021-02-19T12:23:10Z | |
dc.date.available | 2021-02-19T12:23:10Z | |
dc.date.created | 2021-02-18T13:34:52Z | |
dc.date.issued | 2020 | |
dc.identifier.citation | American Journal of Physiology. Regulatory Integrative and Comparative Physiology. 2020, 318 (2), R329-R337. | |
dc.identifier.issn | 0363-6119 | |
dc.identifier.uri | https://hdl.handle.net/11250/2729236 | |
dc.description.abstract | Insulin-like growth factor binding protein (IGFBP)-1a is one of three major circulating forms in salmon and induced under catabolic conditions. However, there is currently no immunoassay available for this form because of a lack of standard and specific antibodies. We developed a time-resolved fluoroimmunoassay (TR-FIA) for salmon IGFBP-1a using recombinant protein for labeling, an assay standard, and production of antiserum. The TR-FIA had a low cross-reactivity (3.6%) with IGFBP-1b, another major form in the circulation. Fasting for 4 wk had no effect on serum immunoreactive (total) IGFBP-1a levels in yearling masu salmon, whereas 6-wk fasting significantly increased it. There was a significant, but weak, negative relationship between serum total IGFBP-1a level and individual growth rate (r2 = 0.12, P = 0.01). We next developed a ligand immuno-functional assay (LIFA) using europium-labeled IGF-I to quantify intact IGFBP-1a. In contrast to total IGFBP-1a, serum intact IGFBP-1a levels increased after 4 wk of fasting, and refeeding for 2 wk restored it to levels similar to those of the fed control. Serum intact IGFBP-1a levels showed a significant negative correlation with individual growth rate (r2 = 0.52, P < 0.001), which was as good as that of IGFBP-1b. Our findings using newly developed TR-FIA and LIFA suggest that regulation of intact IGFBP-1a levels has an important effect on growth in salmon and that intact IGFBP-1a is a negative index of salmon growth. | |
dc.language.iso | eng | |
dc.title | Intact rather than total circulating insulin-like growth factor binding protein-1a is a negative indicator of growth in masu salmon | |
dc.type | Peer reviewed | |
dc.type | Journal article | |
dc.rights.holder | © 2020 the American Physiological Society | |
dc.description.version | publishedVersion | |
cristin.ispublished | true | |
cristin.fulltext | original | |
cristin.qualitycode | 2 | |
dc.identifier.doi | 10.1152/AJPREGU.00099.2019 | |
dc.identifier.cristin | 1891375 | |
dc.source.journal | American Journal of Physiology. Regulatory Integrative and Comparative Physiology | |
dc.source.volume | 318 | |
dc.source.issue | 2 | |
dc.source.pagenumber | R329-R337 | |