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Interleukin-1 inhibits the secretion of gastric acid in rats: possible involvement of prostaglandin 总被引:5,自引:0,他引:5
A Uehara T Okumura C Sekiya K Okamura Y Takasugi M Namiki 《Biochemical and biophysical research communications》1989,162(3):1578-1584
To examine the hypothesis that interleukin-1 may inhibit the secretion of gastric acid, the present study was carried out using pylorusligated rats. Based upon three lines of evidence, we report here that interleukin-1, both endogenously released and exogenously administered, suppresses gastric acid secretion and that the interleukin-1-induced inhibition of acid output is possibly mediated by prostaglandin. First, lipopolysaccharide, a potent stimulant of the release and production of endogenous interleukin-1, caused the suppression of gastric acid, and this response was dose-related. Second, the intraperitoneal injection of interleukin-1 resulted in a dose-related inhibition of gastric acid output. Third, the administration of indomethacin completely blocked the suppression of gastric acid secretion induced by interleukin-1. These results demonstrated for the first time that IL-1 might be involved in the regulation of gastric secretion. 相似文献
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Tominaga Yoshito; Kuchitsu Kazuyuki; Katsuhara Maki; Tazawa Masashi; Miyachi Shigetoh 《Plant & cell physiology》1991,32(2):261-268
Rotational streaming of the cytoplasm including chloroplastswas induced by L-histidine, as well as by light, on the anticlinalface of leaf cells of Egeria densa. In the case of treatmentwith L-histidine some of the chloroplasts remained stationaryon the periclinal face of cells after rotational cytoplasmicstreaming was initiated. However, these chloroplasts were easilydislodged and translocated to the centrifugal end of the histidine-treatedcells by application of a centrifugal force that barely affectedthe location of chloroplasts in cells incubated in the darkwithout L-histidine. This result indicates that the anchoringof chloroplasts was weakened by L-histidine. Thus only the releaseof chloroplasts from anchoring was not enough for initiationof their streaming. The cytoplasmic pH (pHc) and vacuolar pH(pHv) were noninvasively monitored by in vivo 31P-nuclear magneticresonance (NMR) spectroscopy. Compared with the dark controlvalue, both illumination and treatment with L-histidine increasedthe pHc by 0.3 units. In contrast, pHv changed only a littlewith both illumination and treatment with L-histidine. Releaseof chloroplasts from anchoring and initiation of cytoplasmicstreaming are discussed in relation to the increase in pHc inducedby both light and L-histidine.
4 Present address: Department of Cell Biology, National Instituteof Agrobiological Resources, Kannondai, Tsukuba, Ibaraki, 305Japan
5 Present address: Marine Biotechnology Institute Co., Ltd.,Head Office, 2-35-10 Hongo, Bunkyo-ku, Tokyo, 113 Japan (Received July 16, 1990; Accepted December 20, 1990) 相似文献
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Estrogen participation in induction of cervicovaginal adenosis-like lesions in immature mice exposed prenatally to diethylstilbestrol 总被引:2,自引:0,他引:2
The structure of human zygapophyseal joint synovial folds as seen by high-power light microscopy and transmission electron microscopy is described. Small myelinated nerves are demonstrated in association with some capillaries in the synovial folds. This may have clinical significance in the field of spinal pain. 相似文献
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Internodal cells of Chara australis were subjected to two consecutiveintracellular perfusions with a Ca2+-free EGTA medium whichdisintegrated the tonoplast within about 10 minutes and thenwith a Ca2+-buffered medium. All perfusion media usually contained1 mM ATP. To stop the electrogenic pump, the internode was depletedof intracellular ATP. The excitability of the plasmalemma wasnot significantly influenced by intracellular free Ca2+ concentrationsup to 104 M. To trigger action potentials, minimum currentdensities of 1 to 2 µA cm2 had to be applied atall tested Ca2+ concentrations. In the absence of cytoplasmicATP, excitability was completely lost at all Ca2+ concentrations.
1 Present address: Botanisches Institut der Universit?t Bonn,Venusbergweg 22, D-5300 Bonn, FRG. (Received September 22, 1984; Accepted March 6, 1985) 相似文献
7.
Ionic Activity Gradients across the Surface Membrane of Cytoplasmic Droplets Prepared from Chara australis 总被引:1,自引:0,他引:1
The membrane potential and the ionic activity gradients of K+and Cl across the surface membrane of cytoplasmic dropletsprepared from Chara australis internodal cells, were measuredin high and low ionic strength bathing solutions using liquidion exchange microelectrodes selective for K+ and Cl.Our results indicate that K+ is close to electrochemical equilibriumwhereas Cl is not.
1 Present address: ICI Japan, Palace Hotel Annex Building, Marunouchi,Tokyo, Japan. 相似文献
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Development of human pancreas 总被引:2,自引:0,他引:2
Masashi Fukayama Michio Ogawa Yukiko Hayashi Morio Koike 《Differentiation; research in biological diversity》1986,31(2):127-133
The developmental sequence of human pancreatic secretory proteins has not previously been studied in detail. We applied immunohistochemistry to study 20 fetal and neonatal pancreas' (8th to 39th gestational weeks) using antisera against the following pancreatic secretory proteins: pancreatic secretory trypsin inhibitor (PSTI), serine proteinases (trypsin, chymotrypsin, and elastase I), and amylase. PSTI was first detected in developing buds of the pancreas during the 8th gestational week, and proteinases were observed in acinar cells during the 14th week of gestation. Immunoreactivity for both PSTI and proteinases was found in most acinar cells soon after their appearance. Immunoreactivity for amylase could not be detected in fetal or neonatal pancreas tissue. PSTI was also found in developing islets during the 14th gestational week, but the number of immunoreactive cells had decreased by term. Cells positive for serine proteinases were occasionally in contact with islets in second-trimester fetuses. In discussing these results, we give particular attention to the nonparallel appearance of secretory products in the fetal pancreas, and the significance of cells immunoreactive for secretory proteins in endocrine islets. 相似文献
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Microiontophoretic study was performed to elucidate dopaminergic mechanism in the nucleus accumbens (Acc) of rats anesthetized with chloral hydrate. Iontophoretically applied dopamine produced an inhibition of glutamate-induced firing in 28 (62%) out of 45 Acc neurons tested. The dopamine-induced inhibition of 14 Acc neurons was clearly antagonized by simultaneous application of haloperidol, and a partial antagonism by sulpiride was observed in 3 out of 10 Acc neurons. These results indicate that dopamine produces an inhibition of the Acc neuron and that, compared to haloperidol, sulpiride is a less potent blocker of the postsynaptic dopamine receptor involved in the dopamine-induced inhibition. 相似文献