著者
Takuya Murata Shuichi Chiba Mitsumori Kawaminami
出版者
The Japan Endocrine Society
雑誌
Endocrine Journal (ISSN:09188959)
巻号頁・発行日
vol.69, no.3, pp.283-290, 2022 (Released:2022-03-28)
参考文献数
28
被引用文献数
4

Gonadotropin-releasing hormone (GnRH) stimulation of annexin A1 (ANXA1) and A5 (ANXA5) mRNA expression was analyzed in LβT2 gonadotrope cells. Quantitative polymerase chain reaction results showed that a GnRH analog (GnRHa) stimulated the expression of both ANXA1 and A5 mRNA with a peak at 12 h of incubation; however, ANXA1 mRNA was extremely stimulated (60 folds). Immunocytochemical analysis confirmed these findings. A GnRH antagonist inhibited the effect of GnRHa. ANXA1 and A5 mRNA levels were significantly increased by protein kinase C (PKC) activator (12-O-Tetradecanoylphorbol-13-acetate; TPA), but not by dibutyryl cAMP. GnRHa-stimulated induction of ANXA1 and A5 mRNA was inhibited by PKC (GF109203) and MEK inhibitors (PD98059). TPA increased ANXA1 and A5 mRNA expression in a dose-dependent manner (1 nM to 10 μM), while the extent of the increase was much greater in ANXA1. After stimulation with 10 nM or 1 μM TPA, ANXA1 and A5 mRNA levels were increased at 6 h. ANXA1 mRNA levels were higher in the 1 μM TPA than in the 10 nM TPA treatment, whereas 1 μM TPA did not show further stimulation of ANXA5 mRNA compared to 10 nM TPA. These results clearly show that ANXA1 mRNA expression is stimulated by GnRH through PKC like ANXA5, and the response of ANXA1 is much larger than that of ANXA5. A close relationship between these annexins and a significant role for ANXA1 in GnRH action at gonadotropes is suggested.
著者
Masataka Yamamoto Koji Shimatani Masaki Hasegawa Takuya Murata Yuichi Kurita
出版者
The Society of Physical Therapy Science
雑誌
Journal of Physical Therapy Science (ISSN:09155287)
巻号頁・発行日
vol.30, no.8, pp.966-970, 2018 (Released:2018-07-24)
参考文献数
24
被引用文献数
7

[Purpose] The purpose of this study was to investigate the effect of changing the plantar flexion resistance of an ankle-foot orthosis on knee joint reaction and knee muscle forces. Furthermore, the influence of an ankle-foot orthosis with an over-plantar flexion resistance function on knee joint reaction force was verified. [Participants and Methods] Ten healthy adult males walked under the following three conditions: (1) no ankle-foot orthosis, and with ankle-foot orthoses with (2) a strong and (3) a weak plantar flexion resistance (ankle-foot orthosis conditions). The knee flexion angle, quadricep muscle force, hamstring muscle force, and knee joint reaction force during the stance phase were measured using a motion analysis system, musculoskeletal model, and ankle-foot orthosis model. [Results] The peak knee joint reaction force, knee flexion angle, and quadricep muscle force in the early stance phase significantly increased in the strong plantar flexion resistance condition in comparison with the “no ankle-foot orthosis” condition. [Conclusion] Increased knee joint reaction force with over-plantar flexion resistance suggests that over-plantar flexion resistance causes various knee problems such as knee pain and knee osteoarthritis.