• Archives of Pharmacal Research
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• v.21 no.6
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• pp.657-663
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• 1998

The enzyme responsible for the synthesis of nitric oxide (NO) from L-arginine in mammalian tissues is known as nitric oxide synthase (NOS) (EC.1.14.13.39). In the present study, the role of NO in the regulation of exocrine secretion was investigated in rat pancreatic acinar cells. Treatment of rat pancreatic acinar cells with cholecystokinin-octapeptide (CCK-OP) resulted in an increase in the arginine conversion to citrulline, the amount of $NO_X$, the release of amylase, and the level of CGMP. Especially, CCK-OP-stimulated increase of arginine to citrulline transformation, the amount of $NO_X$, and CGMP level were completely counteracted by the inhibitor of NOS, NG-monomethyl-L-arginine (MMA), by contrast, that of amylase release was partially reduced. Furthermore, MMA-induced decrease of NOS activity and amylase release showed dose-dependent pattern. The data on the time course of CCK-OP-induced citrulline formation and CGMP rise indicate that NOS and guanylate cyclase were activated by treatment of CCK-OP. However, the mechanism of agonist-stimulated guanylate cyclase activation in acinar cells remains unknown. Therefore, activation of NOS is one of the early events in receptor-mediated cascade of reactions in pancreatic acinar cells and NO, not completely, but partially mediate pancreatic enzyme exocrine secretion.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.2
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• pp.105-111
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• 2010

Inositol 1,4,5-trisphosphate receptors ($InsP_3Rs$) modulate $Ca^{2+}$ release from intracellular $Ca^{2+}$ store and are extensively expressed in the membrane of endoplasmic/sarcoplasmic reticulum and Golgi. Although caffeine and 2-aminoethoxydiphenyl borate (2-APB) have been widely used to block $InsP_3Rs$, the use of these is limited due to their multiple actions. In the present study, we examined and compared the ability of caffeine and 2-APB as a blocker of $Ca^{2+}$ release from intracellular $Ca^{2+}$ stores and $Ca^{2+}$ entry through store-operated $Ca^{2+}$ (SOC) channel in the mouse pancreatic acinar cell. Caffeine did not block the $Ca^{2+}$ entry, but significantly inhibited carbamylcholine (CCh)-induced $Ca^{2+}$ release. In contrast, 2-APB did not block CCh-induced $Ca^{2+}$ release, but remarkably blocked SOC-mediated $Ca^{2+}$ entry at lower concentrations. In permeabilized acinar cell, caffeine had an inhibitory effect on InsP3-induced $Ca^{2+}$ release, but 2-APB at lower concentration, which effectively blocked $Ca^{2+}$ entry, had no inhibitory action. At higher concentrations, 2-APB has multiple paradoxical effects including inhibition of Ins$P_3$-induced $Ca^{2+}$ release and direct stimulation of $Ca^{2+}$ release. Based on the results, we concluded that caffeine is useful as an inhibitor of $InsP_3R$, and 2-APB at lower concentration is considered a blocker of $Ca^{2+}$ entry through SOC channels in the pancreatic acinar cell.

• Imaging Science in Dentistry
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• v.33 no.3
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• pp.161-169
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• 2003

Purpose: To observe the histologic changes and clusterin expression in the acinar cells of the submandibular gland in streptozotocin-induced diabetic rat following irradiation. Materials and Methods: Mature Sprague-Dawley rats were divided into three groups: control, diabetic, and diabetic-irradiated groups. Diabetes mellitus was induced in the Sprague-Dawley rats by injecting streptozotocin, while the control rats were injected with citrate buffer only. After 5 days, rats in diabetic-irradiated group were irradiated with single absorbed dose of 10 Gy to the head and neck region. The rats were killed at 1, 3, 7, 14,21, and 28 days after irradiation. The specimen including the submandibular gland were sectioned and observed using histologic and immunohistochemical methods. Results : Morphologic change of acinar cells was remarkable in the diabetic group, but was not observed in the diabetic-irradiated group. Necrotic tissues were observed in the diabetic-irradiated group. Coloring of toluidine blue stain was most increased at 14 days in the diabetic group, however there were no significant change throughout the period of the experiment in the diabetic-irradiated group. Expression of clusterin was most significant at 14 days in the diabetic group, but gradually decreased with time after 7 days in the diabetic-irradiated group. Degeneration of clusterin was observed in the diabetic-irradiated group. Conclusion : This experiment suggests that the acinar cells of submandibular gland in rats are physiologically apoptosed by the induction of diabetes, but that the apoptosis is inhibited and the acinar cells necrotized after irradiation.

• Applied Microscopy
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• v.23 no.1
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• pp.25-34
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• 1993

Prolactin has been reported to be present in the tear film of humans and prolactin-like immunoreactivity has been detected by immunofluorescence in acinar cells of the lacrimal glands of humans and rats. The present study was aimed at clarifying the intracellular distribution of the prolactin-like immunoreactivity, using the electron microscope immunogold technique. The lacrimal gland acinar cells have two types of secretory granules: 1) Secretory granules containing flocculent materials irregularly shaped and are often coalesced. 2) Secretory granules are fairly round and contain homogenous materials of a moderate electron density. The density of the granular content varies even within a single cell. We found prolactin-like reactivity in secretory granules, some smaller cytosolic vesicles, Golgi cisternae and nuclei in acinar cells from intact glands of rat. Our present results are consistent with the conclusion that prolactin is present in lacrimal cells. The presence of prolactin reactivity in the nucleus suggests that prolactin may be a regulatory factor modulating gene expression.

• Journal of Chest Surgery
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• v.7 no.1
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• pp.37-46
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• 1974

52 cases of metastatic lung tumor, including 22 [42.3%] choriocarcinoma., 13[25%] liver cancer, 6 [7.5%] stomach cancer, 2 bone tumor, etc, were reviewed at Busan National University Hospital, during a 5 year period ending with 1974. The age distribution of metastatic lung tumor were same in second decade to 5th decade. The most common appearances of roentgenograms of metastatic lung tumor were that of multinodular [42.3%], diffuse acinar [21.1%],infiltrative or pneumonic[21.1%], solitary lesion [9.6%] and diffuse micronodular [5.7%]. The metastatic lesions originated from choriocarcinoma revealed multinodular and acinar in roentgenogram, and the lesions originated from liver and stomach cancer revealed infiltrative and acinar. In our series, the positive hilar lymph node enlargement was encountered in 12 cases, of which 4 were in liver cancer and 3 were in stomach cancer. Pleural effusion was also encountered in 5 cases, of which 3 were in liver cancer. The treatment of this series was almost conservative except of 2 cases of pulmonary resection, and the reason of this limited cases of surgical treatment was seemed due to the delayed direction of metastasis to lung beyond the proper indication of surgery.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.56-56
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• 2003

Isolated single pancreatic acinar cells have long been used as a good model for studying many kinds of signaling processes due to their good structural and functional polarities without a significant validation. In this study, we have examined morphological and functional changes of the dissociated single pancreatic acinar cells by imaging cytosolic Ca$\^$2+/ concentration, exocytosis of granules, and by observing their shapes with confocal microscopy.

• Proceedings of the Korean Biophysical Society Conference
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• 2001.06a
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• pp.27-27
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• 2001

In exocrine acinar cells, $Ca^{2＋}$ -activated Cl$^{[-10]}$ channels in the apical membrane are essential for fluid secretion, but it is unclear whether such channels are important for Cl$^{[-10]}$ uptake at the base. Whole cell current recording, combined with local uncaging of caged $Ca^{2＋}$, was used to reveal the Cl$^{[-10]}$ channel distribution in mouse pancreatic acinar cells, where ~90％ of the current activated by $Ca^{2＋}$ in response toacetylcholine was carried by Cl$^{[-10]}$ .(omitted)

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.2
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• pp.215-223
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• 2018

Intracellular $Ca^{2+}$ mobilization is closely linked with the initiation of salivary secretion in parotid acinar cells. Reactive oxygen species (ROS) are known to be related to a variety of oxidative stress-induced cellular disorders and believed to be involved in salivary impairments. In this study, we investigated the underlying mechanism of hydrogen peroxide ($H_2O_2$) on cytosolic $Ca^{2+}$ accumulation in mouse parotid acinar cells. Intracellular $Ca^{2+}$ levels were slowly elevated when $1mM\;H_2O_2$ was perfused in the presence of normal extracellular $Ca^{2+}$. In a $Ca^{2+}-free$ medium, $1mM\;H_2O_2$ still enhanced the intracellular $Ca^{2+}$ level. $Ca^{2+}$ entry tested using manganese quenching technique was not affected by perfusion of $1mM\;H_2O_2$. On the other hand, $10mM\;H_2O_2$ induced more rapid $Ca^{2+}$ accumulation and facilitated $Ca^{2+}$ entry from extracellular fluid. $Ca^{2+}$ refill into intracellular $Ca^{2+}$ store and inositol 1,4,5-trisphosphate ($1{\mu}M$)-induced $Ca^{2+}$ release from $Ca^{2+}$ store was not affected by $1mM\;H_2O_2$ in permeabilized cells. $Ca^{2+}$ efflux through plasma membrane $Ca^{2+}-ATPase$ (PMCA) was markedly blocked by $1mM\;H_2O_2$ in thapsigargin-treated intact acinar cells. Antioxidants, either catalase or dithiothreitol, completely protected $H_2O_2-induced$ $Ca^{2+}$ accumulation through PMCA inactivation. From the above results, we suggest that excessive production of $H_2O_2$ under pathological conditions may lead to cytosolic $Ca^{2+}$ accumulation and that the primary mechanism of $H_2O_2-induced$ $Ca^{2+}$ accumulation is likely to inhibit $Ca^{2+}$ efflux through PMCA rather than mobilize $Ca^{2+}$ ions from extracellular medium or intracellular stores in mouse parotid acinar cells.

• Applied Microscopy
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• v.35 no.2
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• pp.65-72
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• 2005

The ultrastructure of submandibular gland was examined in the lesser white-toothed shrew, Crocidura suaveolens. The submandibular gland of C. suaveolens was a mixed gland composed of serous and mucous acinar cells. Secretory granules from the acini were discharged through the salivary ducts into the oral cavity. Serous and mucous acinar cells had well developed rough endoplasmic reticulum and mitochondria and large amount of granules. In case of serous acinar granules, an immature granule was formless and had only dense specks, and a matured granule was a complete round type delimiting by a single membrane and had a homogeneous dense center with dense specks on the border. In case of mucous acinar granules, while an immature granule was a round type and had an only homogeneous matrix and an indistinct limiting membrane, a mature granule was an even round type having a variety of pattern with several dense bands into the homogeneous matrix and had a distinct membrane. Therefore, a mature mucous acinar granule of C. suaveolens was not only distinct from those of the other mammalian species to have a variety of pattern but also from those of C. lasiura to have an even round type. A great serous-like secretory granules and Myelin-like body were observed in the cytoplasm and lumen of granular duct cells. Myelin-like body, a characteristic structure only reported in salivary gland of three shrews, was discharged from secretory cell into lumen by the manner of exocytosis which has little differences from discharging manner of secretory granules.

• Journal of Life Science
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• v.23 no.11
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• pp.1404-1408
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• 2013

(-)-Epigallocatechin-3-gallate (EGCG), a green tea polyphenol, has been shown to have strong antibacterial, antiviral, antioxidant, anti-inflammatory, and chemopreventive effects. However it is unknown whether EGCG can recover alcohol-associated pancreatitis. The aim of this study was to investigate the effects of EGCG on pancreatic enzyme activities and the expressions of pancreatic regenerating related markers, such as adenosine monophosphate-activated protein kinase (AMPK), raf-1 kinase inhibitor protein (RKIP), and Regenerating gene 1 (Reg1), in mice pancreatic primary acinar cells. Our results revealed that activities of ${\alpha}$-amylase and chymotrypsin were significantly increased in the cells treated with ethanol compared to the untreated control cells; however, the increased activities of both enzymes were markedly reduced by pretreatment with EGCG. Phosphorylation of AMPK and total expression of RKIP were decreased in the ethanol-treated primary acinar cells; however, these were both significantly increased in the EGCG-pretreated cells. In addition, when EGCG was treated, expression of Reg1 was markedly increased compared with that of the control or the ethanol-treated primary acinar cells, demonstrating that EGCG can modulate pancreatic regenerating related genes. Therefore, our findings suggest that EGCG may have therapeutic utility in the prevention or treatment of alcohol-associated pancreatitis.