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Graduate School of Science / Faculty of Science >
Peer-reviewed Journal Articles, etc >
High Population Density of Juvenile Chum Salmon Decreased the Number and Sizes of Growth Hormone Cells in the Pituitary
| Title: | High Population Density of Juvenile Chum Salmon Decreased the Number and Sizes of Growth Hormone Cells in the Pituitary |
| Authors: | Salam, Md. Abdus Browse this author | | Ota, Yuki Browse this author | | Ando, Hironori Browse this author | | Fukuwaka, Masa-aki Browse this author | | Kaeriyama, Masahide Browse this author →KAKEN DB | | Urano, Akihisa Browse this author |
| Issue Date: | Dec-1999 |
| Publisher: | 日本動物学会 |
| Journal Title: | Zoological Science |
| Volume: | 16 |
| Issue: | 6 |
| Start Page: | 945 |
| End Page: | 954 |
| Abstract: | Juveniles of chum salmon (Oncorhynchus keta) held at high population density were apparently smaller than those held at medium and low population densities. The effects of high population density on pituitary growth hormone (GH) cells in juvenile chum salmon were examined using immunocytochemical and in situ hybridization techniques. The ratio of GH-immunoreactive (ir) area to the whole pituitary was almost constant in all of the high, medium and low population density groups, although the number and sizes of GH-ir cells were decreased in the high population density group. Image-analysis of GH-ir cells indicated the presence of a population of heterogenous cells, in which medium or rather strongly stained smaller cells and as extreme weakly stained larger cells. The medium or rather strongly stained smaller cells predominated in the high population density group, while weakly stained larger cells in the low population density group. In situ hybridization study showed somewhat different distributions and intensities of hybridization signals for mRNAs encoding GH I and II precursors. The area showing signals for GH II mRNA in the high population density group was significantly smaller than those in the medium and low population density groups. In contrast, the sizes of areas showing signals for GH I mRNA did not differ among the groups, although the intensity was slightly higher in the high population density group. These results indicate that high population density decreased the number of weakly immunoreactive larger GH cells, and also suppressed expression of the gene encoding GH II precursor, which may result in retarded somatic growth. |
| Rights: | (c) 日本動物学会 / 本文献の公開は著者の意思に基づくものである |
| Relation: | http://www.bioone.org/perlserv/?request=get-archive&issn=0289-0003 |
| Type: | article |
| URI: | http://hdl.handle.net/2115/32923 |
| Appears in Collections: | 理学院・理学研究院 (Graduate School of Science / Faculty of Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
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Submitter: 浦野 明央
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