著者

Marina Ilicic Trent Butler Tamas Zakar Jonathan W. Paul

出版者

日本平滑筋学会

雑誌

Journal of Smooth Muscle Research (ISSN:09168737)

巻号頁・発行日

vol.53, pp.73-89, 2017 (Released:2017-06-23)

参考文献数

55

被引用文献数

16

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Background: Ex situ analyses of human myometrial tissue has been used to investigate the regulation of uterine quiescence and transition to a contractile phenotype. Following concerns about the validity of cultured primary cells, we examined whether myometrial tissue undergoes culture-induced changes ex situ that may affect the validity of in vitro models. Objectives: To determine whether human myometrial tissue undergoes culture-induced changes ex situ in Estrogen receptor 1 (ESR1), Prostaglandin-endoperoxide synthase 2 (PTGS2) and Oxytocin receptor (OXTR) expression. Additionally, to determine whether culture conditions approaching the in vivo environment influence the expression of these key genes. Methods: Term non-laboring human myometrial tissues were cultured in the presence of specific treatments, including; serum supplementation, progesterone and estrogen, cAMP, PMA, stretch or NF-κB inhibitors. ESR1, PTGS2 and OXTR mRNA abundance after 48 h culture was determined using quantitative RT-PCR. Results: Myometrial tissue in culture exhibited culture-induced up-regulation of ESR1 and PTGS2 and down-regulation of OXTR mRNA expression. Progesterone prevented culture-induced increase in ESR1 expression. Estrogen further up-regulated PTGS2 expression. Stretch had no direct effect, but blocked the effects of progesterone and estrogen on ESR1 and PTGS2 expression. cAMP had no effect whereas PMA further up-regulated PTGS2 expression and prevented decline of OXTR expression. Conclusion: Human myometrial tissue in culture undergoes culture-induced gene expression changes consistent with transition toward a laboring phenotype. Changes in ESR1, PTGS2 and OXTR expression could not be controlled simultaneously. Until optimal culture conditions are determined, results of in vitro experiments with myometrial tissues should be interpreted with caution.

著者

Ryo Katsumata Noriaki Manabe Hiroyuki Sakae Kenta Hamada Maki Ayaki Takahisa Murao Minoru Fujita Tomoari Kamada Hirofumi Kawamoto Ken Haruma

出版者

Japan Society of Smooth Muscle Research

雑誌

Journal of Smooth Muscle Research (ISSN:09168737)

巻号頁・発行日

vol.59, pp.14-27, 2023 (Released:2023-03-21)

参考文献数

68

被引用文献数

1

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Esophageal achalasia is classified into three subtypes according to manometric findings. Since several factors, including clinical characteristics and treatment response, have been reported to differ among the subtypes, the underlying pathogenesis may also differ. However, a comprehensive understanding regarding the differences is still lacking. We therefore performed a systematic review of the differences among the three subtypes of achalasia to clarify the current level of comprehension. In terms of clinical features, type III, which is the least frequently diagnosed of the three subtypes, showed the oldest age and most severe symptoms, such as chest pain. In contrast, type I showed a higher prevalence of lung complications, and type II showed weight loss more frequently than the other types. Histopathologically, type I showed a high loss of ganglion cells in esophagus, and on a molecular basis, type III had elevated serum pro-inflammatory cytokine levels. In addition to peristalsis and the lower esophageal sphincter (LES) function, the upper esophageal sphincter (UES) function of achalasia has attracted attention, as an impaired UES function is associated with severe aspiration pneumonia, a fatal complication of achalasia. Previous studies have indicated that type II shows a higher UES pressure than the other subtypes, while an earlier decline in the UES function has been confirmed in type I. Differences in the treatment response are also crucial for managing achalasia patients. A number of studies have reported better responses in type II cases and less favorable responses in type III cases to pneumatic dilatation. These differences help shed light on the pathogenesis of achalasia and support its clinical management according to the subtype.

著者

Sadanobu ABE

出版者

Japan Society of Smooth Muscle Research

雑誌

Journal of Smooth Muscle Research (ISSN:09168737)

巻号頁・発行日

vol.30, no.3, pp.97-110, 1994 (Released:2010-07-21)

参考文献数

40

被引用文献数

4 4

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Dysmotility of lower esophageal sphincter (LES) is common follwing gastric surgery. This may result in gastroesophageal reflux which freqently seen following gastric surgery. The aim of this study was to determine the effect of various surgical procedures on esophagogastric motility in dog and human. Esophago-gastric motillity was investigated by strain gauge transducers during fasted and fed state in conscious dogs. Motility recordings were performed in three groups of dogs, 1) control dogs, 2) with truncal vagotomized dogs (TV), 3) with selective proximal vagotomized dogs (SPV). In human, manometric recordings were performed before and after gastric surgery (SPV or distal partial gastrectomy). In control animals, lower esophagus and LES contracted simultaneously with each contractions of the stomach during interdigesive moter contractions in fasted state. In fed state, LES showed tonic contractions, while gastric body showed receptive relaxation. These motility pattern of LES was considerd to prevent gastroesophageal reflux in both fasted and fed states. These coordinated LES contractions disappeared following SPV or TV. In human, the amplitude and velocity of esophageal propagating contractions deceased after SPV or distal partial gastrectomy. In conclusion, gastric surgeries such as SPV, TV and/or distal partial gastrectomy caused LES dysmotility. These phenomena explain frequent gastroesophageal reflux following gastric surgery. Suplementation of anti-reflux procedure for gastric surgery should be required in the prevention of gastroeso-phageal reflux following gastric surgery.

著者

高柳 一成 小池 勝夫 佐藤 光利

出版者

Japan Society of Smooth Muscle Research

雑誌

Journal of Smooth Muscle Research (ISSN:09168737)

巻号頁・発行日

vol.28, no.2, pp.35-54, 1992 (Released:2010-07-21)

参考文献数

40

被引用文献数

1 1

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It is generally accepted that the agonists, full agonist and partial agonist, interact with the same receptors according to the classical receptor mechanisms. We tried to modify the drug receptor mechanisms in muscarinic cholinoceptors, α1-adrenoceptors and β-adrenoceptors. In the muscarinic cholinoceptor, there are two subtypes of M3-cholinoceptors, propylbenzilylcholine mustard (PrBCM)-sensitive receptors and PrBCM-resistant ones. The full agonists contract the longitudinal muscle through the interaction of two cholinoceptors, PrBCM-sensitive and-resistant ones, while the partial agonists produce the contrac-tion through only the activation of PrBCM-sensitive ones. Upon activation PrBCM-sensi-tive receptors may use cytosolic Ca2+ more effectively than PrBCM-resistant receptors. In the α1-adrenoceptor, the full agonist induces contraction through both ai A and α1B, subtypes and the partial agonist through only α1A, subtype. The adrenoceptors activated by full agonist may be partly different from that by partial agonist in the arteries. In both the common iliac artery and thoracic aorta treated with the irreversible antagonist, phenoxybenzamine the slopes of schild plots of the results obtained from an antagonism between full agonist (phenylephrine) and α1A-selective competitive antagonist (WB4101) equal to 1, suggesting that phenoxybenzamine preferably interacts with α1B, subtype. In the β-adrenoceptor, the pD2-values of the partial agonists obtained from the concentration-response curves are significantly different from their pA2-values against full agonist (isoprenaline). The Scatchard plot of the specific [3H] befunolol (the partial agonist) binding showed two affinity sites of the receptors in the absence of Gpp (NH) p but the low affinity site was reduced while the high affinity site was not affected in the presence of Gpp (NH) p.The β-adrenergic partial agonists are able to discriminate these two different binding sites of the β-adrenoceptors. Our results suggest that the receptors activated by full agonists are partly different from those by partial agonists in muscarinic cholinoceptors, α1-and β-adrenoceptors, and that the irreversible antagonist can discriminate between the sites interact with full agonists and those with partial agonists in muscarinic cholinoceptors and α1-adrenoceptors.

著者

Kyosuke Sato Daisuke Chino Tomoya Kobayashi Keisuke Obara Seiji Miyauchi Yoshio Tanaka

出版者

日本平滑筋学会

雑誌

Journal of Smooth Muscle Research (ISSN:09168737)

巻号頁・発行日

vol.49, pp.63-77, 2013 (Released:2013-12-05)

参考文献数

39

被引用文献数

1 18

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Inhibitory effects of docosahexaenoic acid (DHA) on blood vessel contractions induced by various constrictor stimulants were investigated in the rat thoracic aorta. The inhibitory effects of DHA were also compared with those of eicosapentaenoic acid (EPA) and linoleic acid (LA). DHA exhibited a strong inhibitory effect on the sustained contractions induced by U46619, a TXA2 mimetic. This inhibitory effect of DHA was not affected by removal of the endothelium or by treatment with either indomethacin or Nω-nitro-l-arginine. DHA also significantly diminished PGF2α-induced contraction but did not show any appreciable inhibitory effects on the contractions to both phenylephrine (PE) and high-KCl. Similarly, EPA exhibited significant inhibitory effects against the contractions induced by both U46619 and PGF2α without substantially affecting either PE- or high-KCl-induced contractions. However, both DHA and EPA generated more potent inhibitions against contractions induced by U46619 than those by PGF2α. In contrast, LA did not show significant inhibitory effects against any contractions, including those induced by U46619. The present findings suggest that DHA and EPA elicit more selective inhibition against blood vessel contractions that are mediated through stimulation of prostanoid receptors than those through α-adrenoceptor stimulation or membrane depolarization. Although DHA and EPA have similar inhibitory potencies against prostanoid receptor-mediated contractions, they had a more potent inhibition against TXA2 receptor (TP receptor)-mediated contractions than against PGF2α receptor (FP receptor)-mediated responses. Selective inhibition by either DHA or EPA of prostanoid receptor-mediated blood vessel contractions may partly underlie the mechanisms by which these ω-3 polyunsaturated fatty acids exert their circulatory-protective effects.

著者

Yoshihiko Kito

出版者

Japan Society of Smooth Muscle Research

雑誌

Journal of Smooth Muscle Research (ISSN:09168737)

巻号頁・発行日

vol.47, no.2, pp.47-53, 2011 (Released:2011-07-15)

参考文献数

33

被引用文献数

8 20

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Intramuscular interstitial cells of Cajal (ICC-IM) are found within the smooth muscle layers of the stomach. ICC-IM are mainly spindle shaped cells with bipolar processes orientated along the long axis of surrounding smooth muscle cells. ICC-IM make close contacts with nerve varicosities and form gap junctions with neighbouring smooth muscle cells, indicating that ICC-IM mediate enteric motor neurotransmission. These morphological properties of ICC-IM are similar throughout the stomach. However, the electrical properties of these cells differ from region to region. In the fundus, ICC-IM generate spontaneous transient depolarizations (STDs), resulting in an ongoing discharge of unitary potentials in the smooth muscle cells. ICC-IM in the corpus generate slow waves and as they fire at the highest frequency they serve as the dominant pacemaker cells in the stomach. On the other hand, ICC-IM in the antrum generate the secondary component of slow waves triggered by the initial component that propagates passively from myenteric ICC (ICC-MY). Thus, the different electrical properties of ICC-IM play a critical role in creating the distinct functions of the proximal and distal regions of the stomach such that the fundus acts as a reservoir of food, the corpus as a dominant pacemaker region, while the antrum acts as a region for mixing and propulsion of food.