- 著者
- Takahiro Tokuhisa Masafumi Yano Masakazu Obayashi Toshiyuki Noma Mamoru Mochizuki Tetsuro Oda Shinichi Okuda Masahiro Doi Jinyao Liu Yasuhiro Ikeda Takeshi Yamamoto Tomoko Ohkusa Masunori Matsuzaki
- 出版者
- The Japanese Circulation Society
- 雑誌
- Circulation Journal (ISSN:13469843)
- 巻号頁・発行日
- vol.70, no.6, pp.777-786, 2006 (Released:2006-05-25)
- 参考文献数
- 42
- 被引用文献数
- 18 20
Background The Ca2+ regulatory proteins in the sarcoplasmic reticulum (SR) play a key role in the pathogenesis of heart failure. In the present study the effect of chronic β-receptor-stimulation on cardiac and SR functions was assessed, with or without angiotensin-II receptor antagonist treatment recently reported to have anti-β-adrenergic activity. Methods and Results Rats were treated with isoproterenol with (+) or without (-) candesartan (CAN) and then SR vesicles were isolated from the left ventricular muscle. Both Ca2+-uptake and the amount of SR Ca2+-ATPase were significantly lower in the CAN (-) group than in the shams, but those were almost normally restored in the CAN (+). Although the level of the protein kinase A (PKA)-phosphorylation of the SR Ca2+ release channel, known as the ryanodine receptor (RyR2), was elevated in the CAN (-), no Ca2+-leak was detected. However, SIN-1 (O2 - donor) induced Ca2+-leak in the CAN (-) at a 10-fold lower dose than in the sham and CAN (+). In cardiomyocytes, SIN-1 decreased cell shortening and the peak Ca2+ transient and prolonged time from peak to 70% decline in CAN (-), again at 10-fold lower dose than in the sham and CAN (+). Conclusion Chronic β-receptor-stimulation did not induce any Ca2+-leak from the SR, whereas Ca2+-leak was easily induced when oxidative stress was applied to the PKA-phosphorylated RyR2. Candesartan not only improved Ca2+-uptake, but also prevented PKA-phosphorylation, rendering the SR less susceptible to Ca2+-leak. (Circ J 2006; 70: 777 - 786)
- 著者
- Noriko Inoue Tomoko Ohkusa Tomoko Nitta Masahiko Harada Kazuya Murata Masunori Matsuzaki
- 出版者
- The Japanese Circulation Society
- 雑誌
- JAPANESE CIRCULATION JOURNAL (ISSN:00471828)
- 巻号頁・発行日
- vol.65, no.11, pp.1001-1003, 2001 (Released:2001-10-25)
- 参考文献数
- 5
- 被引用文献数
- 1
A 26-year-old man had a loss consciousness for a few minutes while smoking in the standing position, and was referred to hospital. No abnormalities were found in a computed tomography examination of his head, in a 24-h electrocardiogram or in an exercise tolerance test. The head-up tilt test (HUT) while tobacco smoking elicited a positive response in the tilted position, but the HUT without tobacco smoking was negative. The most noteworthy effect of tobacco smoking during the HUT was the high level of plasma epinephrine compared to the levels seen during supine smoking or the HUT alone. Syncope induced by tobacco smoking in the standing position is rare and the mechanism may be the same as that underlying neurally mediated syncope. (Jpn Circ J 2001; 65: 1001 - 1003)
- 著者
- Keiko Yamasaki Hiroyuki Sawatari Nao Konagai Chizuko A. Kamiya Jun Yoshimatsu Jun Muneuchi Mamie Watanabe Terunobu Fukuda Atsushi Mizuno Ichiro Sakamoto Kenichiro Yamamura Tomoko Ohkusa Hiroyuki Tsutsui Koichiro Niwa Akiko Chishaki
- 出版者
- The Japanese Circulation Society
- 雑誌
- Circulation Journal (ISSN:13469843)
- 巻号頁・発行日
- vol.83, no.11, pp.2257-2264, 2019-10-25 (Released:2019-10-25)
- 参考文献数
- 38
- 被引用文献数
- 5
Background:The average maternal age at delivery, and thus the associated maternal risk are increasing including in women with congenital heart disease (CHD). A comprehensive management approach is therefore required for pregnant women with CHD. The present study aimed to investigate the factors determining peripartum safety in women with CHD.Methods and Results:We retrospectively collected multicenter data for 217 pregnant women with CHD (age at delivery: 31.4±5.6 years; NYHA classifications I and II: 88.9% and 7.4%, respectively). CHD severity was classified according to the American College of Cardiology/American Heart Association guidelines as simple (n=116), moderate complexity (n=69), or great complexity (n=32). Cardiovascular (CV) events (heart failure: n=24, arrhythmia: n=9) occurred in 30 women during the peripartum period. Moderate or great complexity CHD was associated with more CV events during gestation than simple CHD. CV events occurred earlier in women with moderate or great complexity compared with simple CHD. Number of deliveries (multiparity), NYHA functional class, and severity of CHD were predictors of CV events.Conclusions:This study identified not only the severity of CHD according to the ACC/AHA and NYHA classifications, but also the number of deliveries, as important predictive factors of CV events in women with CHD. This information should be made available to women with CHD and medical personnel to promote safe deliveries.