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

寿田 鳳輔 藤井 久四郎 新井 和夫 丸岡 利市 斎藤 仁隆

出版者

Japan Society of Smooth Muscle Research

雑誌

日本平滑筋学会雑誌 (ISSN:03743527)

巻号頁・発行日

vol.4, no.2, pp.191-202, 1968

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The spontaneous and oxytocin induced electrical activity of the pregnant uterus of rat has been studied <I>in vivo</I> by recording electromygorams at various stages during pregnancy. The electrical activity has been compared at different uterine portions in the pregnant uterus of rat; at the myometrium of the corpus, the cervix, the edge of the placental area, and the placental area. Also, one or two electrodes (silver wire, 50μ in diameter) were introduced into the myometrial coat at the different uterine poitions for the recording as described in the previous report. The experiments were performed on the 12th, 13th, 14th, 18th and 21st days of pregnancy. The electrical activity of the pregnant rat uterus consisted of repetitive spike discharges at the different uterine portions through various stages of pregnancy. <I>In vivo</I>, myometrium of the placental area showed a little spontaneous activity before term, but there was no difference between the myometrium of the edge of the placental area and of the other portions (the corpus and the cervix). No distinction between the electrical excitability of placental and nonplacental myometrium was observed at term. After the above control records were taken, oxytocin was injected in a dose of 2 or 3 i.u. intraumuscularly and the response in increase of spike discharges at the different uterine portions were clearly detected.

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

ファラマル アシュリー 日高 弘義 高井 章 富田 忠雄

出版者

Japan Society of Smooth Muscle Research

雑誌

日本平滑筋学会雑誌 (ISSN:03743527)

巻号頁・発行日

vol.21, no.1, pp.57-69, 1985

被引用文献数

4

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Aschoori, F., Hidaka, H., Takai, A. & Tomita, T. <I>Contraction of smooth muscle in Ca-free solution</I>. Japanese Journal of Smooth Muscle Research, 1985, 21 (1), 57-69.-The tonic contractions which are extremely resistant to removal of the external Ca were investigated in the rat was deferens and myometrium. Both the noradrenaline response in the was deferens and the oxytocin response in the myometrium could be repeatedly produced without appreciable diminution in Ca-free solution for more than 24hrs. On the other hand, the tissue Ca content decreased exponentially after Ca-removal with a half time of 130-180min. When Ca was readmitted, no indication of the early transient contraction was observed in the subsequent response in Ca-free solution, but the response was reduced compared with the response before Ca readmission. Verapamil suppressed the response in the presence of Ca, while it had very weak inhibitory effect even at 10μM. Calmodulin antagonists of phenothi-azine derivatives had a strong inhibitory effect on Ca-induced contractions, whereas they had very weak effects on the receptor-mediated contraction in Ca-free solution. Another calmodulin antagonist, W-7 suppressed both Ca-induced contraction and the contractions independent of external Ca. HA-1004, a vasodilator which has a struc-ture similar to W-7, reduced the receptor-mediated contraction in Ca-free solution without much effect on Ca-induced contractions. These results may suggest that the receptor-mediated contractions resistant to Ca-removal are caused by some process without a contribution of the Ca-calmodulin system.

著者

寿田 鳳輔 藤井 久四郎 新井 和夫 丸岡 利市 斎藤 仁隆

出版者

Japan Society of Smooth Muscle Research

雑誌

日本平滑筋学会雑誌 (ISSN:03743527)

巻号頁・発行日

vol.4, no.1, pp.37-45, 1968

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Albino rats of Wistar strain with normal sexual cycle on the basis of their vaginal smears were used and anesthetized with Mintal (pentobarbital) injecting 5 mg/100 g intraperitoneally in acute experiments. Spontaneous electromyographic activity of the rat uterus <I>in vivo</I> was recorded using a concentric electrode (silver wire, 50μ diameter). One electrode was placed in the tubal side and the other electrode in the cervical side of a corpusuteri of the rat. Electromyographic recordings were made with a 2 channel inkwritingapparatus. The spontaneous electrical activity of the rat uterus <I>in situ</I> could be observed through the cycle. The basic electromyographic patterns of the nonpregnant ratuterus at the estrus were the train of spike and the spike burst. From proestrus to estrus, the spontaneous spike discharges increased in amplitude and in frequency and became of a set of their discharges. In some cases the spontaneous spike discharges were observed sporadically at the diestrus of the cycle and the castrated condition.

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.