著者

Mikihiro Kase Takayuki Shimizu Keita Kamino Kazuo Umetsu Hideki Sugiyama Takashi Kitano

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.17-00004, (Released:2017-06-30)

被引用文献数

5

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The brown hagfish (Eptatretus atami) is one of several known hagfish species occurring in Japanese coastal waters. To date, there has been no research studying genetic polymorphisms in the species. In the present study, we analyzed differences in nucleotide sequences between two populations: one from Suruga Bay on the Pacific coast of Honshu, Japan, and the other from the Sea of Japan, off Akita on the northwest coast of Honshu. We sequenced part of the cytochrome oxidase subunit 1 gene (COX1) from the mitochondrial genome, and three G protein-coupled receptor genes from the nuclear genome. Phylogenetic networks of all four genes showed divergence between the two populations. Further, comparison of the COX1 data using a phylogenetic tree for a range of hagfish species indicated clear differences between the populations, suggesting that they differ at the species level. The numbers of their teeth, in particular of fused cusps (anterior/posterior multicusps), also supported these findings. Individuals of the Suruga Bay population had 3/3 fused cusps, as described for E. atami, whereas individuals of the Akita population had 3/2 fused cusps. These results suggest that the brown hagfish from the Sea of Japan, off the northwest coast of Honshu, is a distinct species from E. atami.

著者

Mikihiro Kase Takayuki Shimizu Keita Kamino Kazuo Umetsu Hideki Sugiyama Takashi Kitano

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.92, no.4, pp.197-203, 2017-08-01 (Released:2018-02-10)

参考文献数

29

被引用文献数

5

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The brown hagfish (Eptatretus atami) is one of several known hagfish species occurring in Japanese coastal waters. To date, there has been no research studying genetic polymorphisms in the species. In the present study, we analyzed differences in nucleotide sequences between two populations: one from Suruga Bay on the Pacific coast of Honshu, Japan, and the other from the Sea of Japan, off Akita on the northwest coast of Honshu. We sequenced part of the cytochrome oxidase subunit 1 gene (COX1) from the mitochondrial genome, and three G protein-coupled receptor genes from the nuclear genome. Phylogenetic networks of all four genes showed divergence between the two populations. Further, comparison of the COX1 data using a phylogenetic tree for a range of hagfish species indicated clear differences between the populations, suggesting that they differ at the species level. The numbers of their teeth, in particular of fused cusps (anterior/posterior multicusps), also supported these findings. Individuals of the Suruga Bay population had 3/3 fused cusps, as described for E. atami, whereas individuals of the Akita population had 3/2 fused cusps. These results suggest that the brown hagfish from the Sea of Japan, off the northwest coast of Honshu, is a distinct species from E. atami.

著者

Jun Hamano Takayuki Shimizu Katsunori Tsuji Wendy M Kohrt Izumi Tabata

出版者

The Japanese Society of Physical Fitness and Sports Medicine

雑誌

The Journal of Physical Fitness and Sports Medicine (ISSN:21868131)

巻号頁・発行日

vol.10, no.3, pp.129-137, 2021-05-25 (Released:2021-05-13)

参考文献数

39

被引用文献数

1 6

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Increased serum parathyroid hormone (PTH) during moderate-intensity exercise has been reported, suggesting that such exercise may stimulate bone resorption. This study was undertaken to observe the effects of exhausting high-intensity intermittent exercise (HIIE) on serum PTH and on blood parameters that may affect PTH secretion during exercise. Seven young trained adults exercised on 2 days after overnight fasting. On the HIIE day, they performed 6–7 exhausting bouts of 20-sec bicycle exercise (intensity, 170% VO2max) with intervening 10-sec rests. On the moderate-intensity exercise (MIE) day, the subjects biked for 60 min at 70% VO2max. The peak lactate concentration in blood after the HIIE was 15.2 ± 1.3 mmol/l. The blood lactate concentration at the end of the MIE was 2.2 ± 0.9 mmol/l. The HIIE significantly reduced the serum PTH (Pre: 30 ± 5 pg/ml, 10 min post-HIIE: 22 ± 4 pg/ml, p < 0.05), whereas the MIE significantly elevated the serum PTH. The HIIE induced a significant increase in serum ionized Ca (iCa); but MIE did not affect iCa. The serum cortisol concentration post-MIE was significantly higher than that observed pre-exercise; no changes from the pre-exercise value were noted post-HIIE. The serum phosphate concentration immediately post-HIIE increased significantly to the same level as that post-MIE. No changes in serum C-terminal telopeptide of Type I collagen (a marker of bone resorption) was observed after the HIIE or MIE. Although these results do not identify stimulator(s) for PTH secretion during HIIE and MIE, they indicate that HIIE does not induce an exercise-induced increase in PTH (which might deteriorate bone metabolism).