The immunohistochemical demonstration of the Thiol: proteindisulfid oxidoreductase (TPO) in pancreas and isolated Langerhans'islets. A light-, fluorescent- and electron microscopic study (author's transl)]

Thiole: Protein disulfide Oxidoreductase (E. C. 1.8.4.2) is capable of catalyzing thiole-disulfid exchange reactions and might have an important function in both protein biosynthesis and degradation. By using histochemical methods we were able to demonstrate the localization of this enzyme in the Langerhans'islets and in the acinus cells of rat pancreas. The reaction of the acinus cells, however, was much weaker than that of the islets. Electron microscopic experiments revealed the enzyme to be located in the outer membrane of the nucleus, in the membranes of the endoplasmic reticulum and B-cell granules, and in the plasmalemma also. All these structures are known to be involved in the insulin biosynthesis and secretion. There is a good correlation between morphological and biochemical findings. In acinus cells there are a few reaction in the outer nucleus membrane, the membranes of the endoplasmatic reticulum, and the plasmalemm.     

胰组织结构提示多肽胰岛素的正常转运经淋巴而非门脉途径

目的　探讨胰岛多肽激素释放形式和细胞外正常转运途径的结构基础。方法　对大鼠和人胰尾部组织进行了光镜 (LM )和透射电镜 (TEM)观察。结果　胰组织主要由腺泡构成的腺小叶和分隔腺小叶的结缔组织所组成。胰腺的导管、血管和淋巴管 ,有髓和无髓神经纤维 ,均穿行于胰结缔组织内。在胰岛周围的结缔组织间隙内也可见到完整的膜包分泌颗粒 (2 0 0～ 5 0 0nm)。胰腺的毛细血管为窗孔 (5 0nm)型。结论　胰组织结构特点提示 :胰岛多肽激素的释放形式 ,可能是连同颗粒膜的整体释放而非传统认为的胞吐分泌 ;释放入胰组织液中的多态胰岛素或分泌颗粒 ,更易进入淋巴而非门脉血液     

人胎胰腺GnRH免疫反应细胞

目的：探讨促性腺激素释的激素(GnRH)免疫反应细胞在人胎胰腺的存在部位和数量变化。方法：用免疫组织化学SABC法，对37例第10-32w人胎胰腺内的GnRH-IR细胞进行观察，并用体视方法分析其数量变化。结果：人胎胰腺GnRH-IR细胞出现于第13w，其数密度随胎龄增加而增大；分布于胰岛及外分泌部的腺泡上皮、导管上皮细胞间。位于胰岛的GnRH-IR细胞呈圆形、卵圆形或多边形。位于腺泡上皮细胞间的GnRH-IR细胞多为锥体形，外分泌部的GnRH-IR细胞均为开放型细胞。结论：胰腺GnRH-IR细胞于胚胎第13w出现，广泛存在于内、外分泌部，其数量随胎龄增加而增加。     

兔胰腺外分泌部的扫描电镜观察——DMSO冷冻割断法

本文以二甲亚砜(dimethyl sulfoxide,DMSO)冷冻割断技术处理正常兔胰腺,在扫描电镜下研究胰腺外分泌部超微结构。兔胰腺外分泌部由许多腺泡组成,每一腺泡由5～6个锥形细胞围绕形成,中央为腺泡腔。腺细胞顶端有短小微绒毛。细胞核呈球形,位于细胞基底部,核内含有1～3个核仁。细胞基底部有大量粗面内质网,呈纵行或同心圆形排列,线粒体介于其间。粗面内质网常自细胞基底部伸向细胞核上端,表面附着核蛋白体。细胞核上端有丰富的高尔基复合体,周周可见散在的球状酶原颗粒。     

Fine structure and immunocytochemistry of cells within the endocrine pancreas of larval and adult sea lampreys,Petromyzon marinus L.

Immunocytochemistry with protein A-gold and routine electron microscopy were used to identify cell types within the endocrine pancreas of larvae, juvenile adults, and upstream-migrant adults of the sea lamprey, Petromyzon marinus. The larval pancreatic islets are composed only of insulin-immunoreactive B-cells, which are uniform in their fine structure. The cranial and caudal pancreatic tissue in both adult periods contains three cell types: B-cells, somatostatin-immunoreactive D-cells, and a third cell type of unknown content. No glucagon-immunoreactive cells are present in lampreys, but B-and D-cells exist in equal numbers in the pancreatic tissue of adults. The B-cells of adults have a fine structure similar to those in larvae. D-cells have secretory granules that are distinctly different from those both in B-cells and in the third cell type. Although B- and D-cells in lamprey pancreatic tissues have a basic morphological similarity to these cells in other vertebrates, their granules are generally of smaller dimensions. The inclusion of granules within large pleomorphic bodies in many D-cells indicates that granule turnover is common. Immunocytochemistry will be a useful tool for showing the relationship between the cells in the degenerating bile ducts and those of the developing adult pancreas.     

Localization of kallikrein and its relation to other trypsin-like esterases in the rat pancreas. A comparison with the submandibular gland.

Kallikrein was located by the direct immunofluorescence technique to the granule-containing luminal portion of pancreatic acinar cells. For the demonstration of the intracellular distribution of pancreas kallikrein, in vivo fixation of the gland was necessary. No kallikrein was found in the duct cells or in the islets of Langerhans. Quantitation by single radial immunodiffusion showed that the concentration of kallikrein in the presence was 1.32 +/- 51 microgram/g wet weight, i.e. 1/91 that of the rat submandibular gland. Bz-Arg-OEt-esterases were in the pancreas found as pro-enzyme but as active enzyme in the submandibular gland. Trypsin-like esterases, hydrolyzing epsilon-amino caproic acid naphtol-AS-D.HBr (ACA), were found in the active form in both submandibular gland and pancreatic homogenates. The submandibular gland contained per g wet weight 6 times as much ACA-esterase activity as the pancreas. In the submandibular gland, kallikrein and ACA-esterase activity were found together in practically all granular tubular cells. Thus, the granular tubular cell contains kallikrein as well as other trypsin-like enzymes like the ACA-esterase, and is in this way comparable to the pancreatic acinar cell. An extraglandular function of kallikrein is suggested for the pancreas in contrast to other kallikrein-containing exocrine organs.     

Light- and electron-microscopic studies on isolated bovine islets of Langerhans.

While several recent studies have focussed on the critical assessment of yield, purity and function of isolated islets, fine-structural investigations of isolated islets have been the subject of only a few studies. After intraductal injection of collagenase solution, the distended bovine pancreata were processed in a continuous digestion-filtration device, after which the purification of the islet suspension was accomplished by density gradient centrifugation. Purified islets were then prepared for light- and transmission electron-microscopic analysis. In semithin sections, no evidence of either connective tissue or exocrine tissue surrounding isolated islets was found. Endocrine cells exhibiting cytoplasmic granules were packed in clusters varying in size. In ultrathin sections, A-cells containing numerous secretory granules were distinctive; their cytoplasm contained conspicuous formations of rough endoplasmatic reticulum and juxtanuclear Golgi complexes. In the B-cells, the Golgi complexes were also prominent; these elements, however, were poor in endoplasmic reticulum and displayed characteristic B-cell granules surrounded by a halo. A few ultrastructurally heterogeneous cells were scattered among the identified cellular elements.     

Exocrine pancreatic insufficiency syndrome in CBA/J mice. Ultrastructural study.

The pathogenesis of a spontaneously occurring exocrine pancreatic insufficiency (EPI) syndrome in CBA/J mice was studied at the ultrastructural level. Initial cytologic manifestations of this syndrome are seen as a progressive digestion of the zymogen granules, beginning at the periphery and proceeding toward the granule interior. Granule membrane breakdown, fusion of neighboring granules, and a release of zymogen contents into the cytoplasm are frequently observed in later stages; in some cases the entire granule contents appear digested before membrane breakdown is observed. In either case, pathologic changes are subsequently observed in mitochondria and rough endoplasmic reticulum. Remnants of lysed cells are then engulfed by invading macrophages, and infiltration by fat cells is observed. Secretory ducts and islets of Langerhans show no pathologic changes even after total autolysis of the exocrine pancreas. Morphologic evidence showing zymogen granule destabilization, coupled with biochemical evidence presented in an accompanying paper, indicate that intracellular autodigestion is the mechanism of exocrine cell death.     

Localization of kallikrein and its relation to other trypsin-like esterases in the rat pancreas. A comparison with the submandibular gland

Kallikrein was located by the direct immunofluorescence technique to the granule-containing luminal portion of pancreatic acinar cells. For the demonstration of the intracellular distribution of pancreas kallikrein, in vivo fixation of the gland was necessary. No kallikrein was found in the duct cells or in the islets of Langerhans. Quantitation by single radial immunodiffusion showed that the concentration of kallikrein in the pancreas was 132 ± 51 μg/g wet weight, i.e. 1/91 that of the rat submandibular gland. Bz-Arg-OEt-esterases were in |the pancreas found as pro-enzyme but as active enzyme in the submandibular gland. Trypsin-like esterases, hydrolyzing σ-amino caproic acid naphtol-AS-D- HBr (ACA), were found in the active form in both submandibular gland and pancreatic homogenates. The submandibular gland contained per g wet weight 6 times as much ACA-esterase activity as the pancreas. In the submandibular gland, kallikrein and ACA-esterase activity were found together in practically all granular tubular cells. Thus, the granular tubular cell contains kallikrein as well as other trypsin-like enzymes like the ACA-esterase, and is in this way comparable to the pancreatic acinar cell. An extraglandular function of kallikrein is suggested for the pancreas in contrast to other kallikrein-containing exocrine organs.     

An immunohistochemical examination of cinnamon extract administration on distribution of NGF (nerve growth factor) and Trk-A (tyrosine kinase-A) receptor for diabetic rats with pancreatic tissue

Background/aim The aim of this study was to investigate the administration of cinnamon extract that is known to be effective in decreasing the high blood glucose and the distribution of NGF and Trk-A receptor in pancreas with immunohistochemistry way.Materials and methods The experimental groups were defined as control, sham, cinnamon, diabetes, and diabetes-cinnamon. At the end of the experiment, the pancreatic tissue samples were obtained for the rats. The hematoxylin-eosin and triple staining were used to examine histology. The immunohistochemical methods were performed on the sections of pancreatic tissue. In all groups, the body weight and fasting blood glucose obtained from the male and female rats and the values were statistically evaluated.Results The NGF immunoreactivity was observed in acinus, excretory pars, excretorius ducts, and islets of Langerhans for the pancreatic tissues of female and male rats in all groups. The Trk-A immunoreactivity was observed in acinus and islets of Langerhans for the pancreatic tissues of female and male rats in the control, sham, and cinnamon groups.Conclusion As a result, it was determined that the cinnamon, which is effective on blood glucose levels, has a positive effect on the NGF production in pancreas.     

Stereological analysis of normal rabbit pancreatic islets

Stereological methods were applied to obtain morphometric data related to pancreatic islets of Langerhans in the normal rabbit. By light microscopy, it was found that 1 mm³ of pancreatic parenchyma contained 47.7 islets, constituting 2.2% of its volume. Approximately 69% of the islets had diameters less than 80 μm; 31% were greater than 80 μm. The former group of islets, however, composed only 13% of the volume of the endocrine pancreas and the latter group, 87%. Using electron microscopy, a unit volume of islet tissue was observed to consist of 86% beta cells, 7.7% alpha cells, and 2.2% delta cells. The average beta-cell volume was 1260 μm³ and its cytoplasm consisted of 52.6% matrix, 12.7% rough endoplasmic reticulum, 10.2% secretory granules, 7.8% mitochondria, and 3.3% Golgi apparatus. A typical beta cell contained 662 mitochondria, intermediate (10-nm) filaments whose length totalled 50 mm, and 9,200 secretory granules with a ratio of four mature granules to each immature or “pale” granule. Within alpha and beta cells, three parameters were used for the quantitation of organelles or their component parts: (1) volume; (2) surface; and (3) numerical densities. In the beta cell, the surface densities of rough endoplasmic reticulum and Golgi membranes exceeded, by two- or threefold, their counterparts in alpha cells. Similarly, the number of beta-cell mitochondria exceeded by 30% that of alpha cells; but beta-cell mitochondrial volume was twice that of the alpha cell, as were surface densities of both inner and outer mitochondrial membranes. Volume and surface densities of secretory granules within beta cells were half the values obtained for alpha cells. An alpha cell contained three times the number of granules present in a beta cell.     

Argyrophil cells in the exocrine pancreas.

The silver positive cells of the exocrine pancreas and primary pancreatic cancers were studied with the Grimelius silver stain and the Fontana-Masson technique. In the pancreas, cells containing black granules with the Grimelius method, which at the same time react negative to Fontana-Masson, are considered argyrophil. These cells were present in the basal portion of some of the acinar tissue and in the ductal epithelia, as well as in the A cells of islets. The incidence and distribution of these argyrophil cells were also studied in a variety of ductal lesions. In the so-called ductal proliferation numerous numbers of positive cells were found. Argyrophil cells were frequently situated in the basal portion of ductal squamous cell metaplasia. In goblet cell metaplasia the numbers were few, and less than in normal ducts. We concluded that the distribution and incidence of argyrophil cells in the ductal epithelia is related to chronic pancreatitis, and in particular to regenerative processes. The incidence of argyrophil cells in primary pancreatic cancer, excluding islets cell origin, was 18 per 41 cases (43.4%). We considered them pancreatic cancer with argyrophil cells.     

The effects of reserpine on the ultrastructure and secretory responses of rat exocrine pancreas.

The effects of chronic reserpine administration on rats mimic in several respects the exocrine dysfunction observed in cystic fibrosis. This drug treatment has been proposed as a model for the human disease. In cystic fibrosis, the pancreas is usually a major organ involved pathologically. The present study was designed to investigate the fine-structural morphology and secretory responses of the pancreas of rats treated chronically with reserpine. Reserpine treatment resulted in increased storage of zymogen granules in pancreatic acinar cells and an apparently reduced ability to discharge these granules following stimulation with cholecystokinin. In addition, granule storage may have produced feedback inhibition on the protein synthesizing machinery as manifested by a slight reduction of rough endoplasmic reticulum. Many acinar cells also had autophagic bodies, suggesting the degradation of excess secretory material. Cholecystokinin stimulation of both control and reserpine-treated rats resulted in the appearance of large vacuoles containing myelin figures and granular material, numerous autophagic bodies (cytosegresomes), and a slight decrease of rough endoplasmic reticulum in pancreatic acinar cells. Secretin stimulation did not cause large vacuole formation, but did cause cytosegresome formation in acinar cells. Large vacuoles in intralobular ducts were noted after reserpine treatment, but were also present after stimulation of untreated pancreas with cholecystokinin.     

Fine structure of the ventral and dorsal lobes of the prostate in the young adult syrian hamster,Mesocricetus auratus

The normal ventral and dorsal prostatic lobes of the young adult Syrian hamster were examined at the light and electron microscopic levels. Each lobe is composed of branched tubular secretory units separated from each other by loose interacinar connective tissue and draining into the urethra. The lumen of each acinus is lined by a simple epithelium composed of columnar secretory cells with occasional small basal cells. The epithelial layer, with the thin underlying lamina propria, forms a mucosa that is often highly folded. The whole acinus is bounded by a thick muscular stroma. In each of the ventral lobes, there are three main ducts, each one formed of tubular branched tributary secretory units. The walls of the secretory acini are moderately folded. Microvilli dominate the lumenal surface of the secretory epithelial cells. The Golgi complex is very extensive and shows dilated cisternae and secretory vesicles and vacuoles of various sizes. Membrane-bounded secretory granules populate the Golgi and apical areas and are released into the acinar lumen by exocytosis. The rough endoplasmic reticulum is dispersed throughout the cytoplasm, except in the region of the Golgi apparatus. In each of the dorsal lobes, there are several main tubular ducts that open into the urethra. Both proximal (ductal) and distal portions of the glandular tree are secretory in nature. Microvilli and cytoplasmic bulges and blebs dominate the lumenal surface of the secretory cells. The cells are also characterized by highly dilated cisternae of rough endoplasmic reticulum. The secretory cells show heterogeneity in the degree of dilation and distribution of rough endoplasmic reticulum, and this heterogeneity may reflect location in the glandular tree. Large dilated cisternae with irregular outlines are common in the basal portion of some cells, mainly those of the distended proximal (ductal) portions of the acini. The more highly folded distal portions of acini show smaller regular cisternae distributed throughout the cytoplasm. The Golgi complex is poorly to moderately developed, and membrane-bounded secretory granules are absent or sparse. Apocrine secretion predominates in the dorsal lobe.     

Proliferation and differentiation of pancreatic β-cells: ultrastructural analysis of the pancreas in diabetic mice induced by selective alloxan perfusion

To clarify the mechanism of regenerative processes of pancreatic β-cells, we constructed a new diabetic model of mice and investigated their pancreatic endocrine cells by electron microscopy. Male ICR mice (8 weeks old) were partially and chemically depancreatized by perfusing alloxan (100 mg/kg body weight) via the caudal vein after clamping the cranial mesenteric artery. By this method, we could render the mice diabetic by partial reduction of β-cells localized in the splenic, gastric, and parabiliary segment. Glucose intolerance gradually ameliorated without any treatment. In the perfused segments, pancreatic β-cells showed pyknosis and the mitochondria were swollen 6h after the treatment, while non-β-cells including α-cells remained intact. At 5 days, β-cells were few and the islets became smaller in size. At 20 weeks, small islet cell clusters (ICCs) were observed budding from interlobular and intralobular ductal epithelial cells. β-cells scattering in the exocrine pancreas were also frequently observed. In the alloxan-nonperfused segment, β-cells with thin rough endoplasmic reticulum and immature secretory granules without an electron-opaque halo were observed, and the number of mitochondria increased in some β-cells at 1 day and 5 days after the treatment. At 20 weeks, β-cells that contained only mature granules were observed in hypertrophic islets. In this model, both proliferation of residual β-cells and differentiation of pancreatic endocrine cells from the ductal epithelial cells were recognized.     

ARGYROPHIL CELLS IN THE EXOCRINE PANCREAS

The silver positive cells of the exocrine pancreas and primary pancreatic cancers were studied with the Grimelius silver stain and the Fontana-Masson technique. In the pancreas, cells containing black granules with the Grimelius method, which at the same time react negative to Fontana-Masson, are considered argyrophil. These cells were present in the basal portion of some of the acinar tissue and in the ductal epithelia, as well as in the A cells of islets. The incidence and distribution of these argyrophil cells were also studied in a variety of ductal lesions. In the so-called ductal proliferation numerous numbers of positive cells were found. Argyrophil cells were frequently situated in the basal portion of ductal squamous cell metaplasia. In goblet cell metaplasia the numbers were few, and less than in normal ducts. We concluded that the distribution and incidence of argyrophil cells in the ductal epithelia is related to chronic pancreatitis, and in particular to regenerative processes. The incidence of argyrophil cells in primary pancreatic cancer, excluding islets cell origin, was 18 per 41 cases (43.4%). We considered them pancreatic cancer with argyrophil cells. ACTA PATH. JAP. 29 : 413–419, 1979.     

Simultaneous alpha-1-antitrypsin accumulation in liver and pancreas

Inclusions positive for periodic acid-Schiff, resistant to diastase, and immunoreactive to alpha-1-antitrypsin (AAT) were found in hepatocytes and pancreatic islet cells of a patient with clinical and pathologic features of AAT deficiency. Alpha-1-antitrypsin was detected in all pancreatic islets, and AAT-positive cells were observed in the excretory pancreatic ducts. These findings suggest that the pancreas synthesizes AAT and possibly serves as a "storage" place in AAT deficiency. Intercalated cells in the excretory pancreatic ducts may be an additional source of AAT.     

An immunohistochemical study on the pancreatic endocrine cells of the three-toed sloth, Bradypus variegatus.

The cellular composition and relative frequency of the occurrence of pancreatic endocrine cells were studied immunohistochemically in a primitive eutherian and arboreal folivore, the three-toed sloth, since previous histochemical and ultrastructural studies on the endocrine pancreas of the sloth have detected only a single islet cell type, the A cell. In the sloth pancreas, four types of endocrine cells immunoreactive for glucagon, insulin, somatostatin and serotonin (5-hydroxytryptamine) were found as reported in the pancreas of human and common experimental mammals, but pancreatic polypeptide-immunoreactive cells were not detected by either avian- or bovine-pancreatic polypeptide antiserum. The endocrine cells were distributed mainly in the islets and partly also in the exocrine tissue including the pancreatic ducts. Larger or smaller clusters consisting of glucagon- and insulin-immunoreactive cells were also found frequently in the interlobular connective tissue. In the islets, glucagon- and insulin-immunoreactive cells were the most prominent cell type, while somatostatin- and serotonin-immunoreactive cells were sparse. The most striking feature in the sloth pancreas is the high frequency of glucagon-immunoreactive cells, because these cells are by far less in number than insulin-immunoreactive cells in the islets of human and common experimental mammals. This appears to be an intriguing characteristic of the sloth pancreas in a possible relation to the animal's unique metabolic system and the phylogenetical position.     

胰抑素在人,猪和豚鼠胰腺分布的免疫组织化学研究

胰抑素(pancreastatin,PS)是一种具有抑制胰岛分泌作用的新肽。本研究用ABC免疫染色法,在Bouin液固定的常规石蜡切片上,研究了胰抑素在豚鼠,猪和人胰腺内的定位和分布,并用相邻切片双标记法,观察了它与胰岛素的共存关系。结果发现,在人胰腺胰抑素样免疫反应(PLI)细胞主要分布于胰岛的周边部。在猪和豚鼠,大部分胰岛细胞呈阳性胰抑素样免疫反应。用相邻薄切片免疫染色技术证明,猪和豚鼠的PLI细胞主要是B细胞。在3个种属胰腺外分泌部的导管和腺泡等处,也均见有PLI细胞分布,在豚鼠胰腺尤为多见。本文对胰抑素在3个种属胰腺不同分布方式的意义进行了讨论。     

Intraperitoneal transplantation of pancreatic anlagen

To determine whether embryonic pancreatic anlagen transplanted to an intraperitoneal site in adult hosts grow, differentiate, and function, we implanted pancreas from embryonic day (E) 12.5 Lewis rat embryos into the omentum of adult Lewis rats or C57Bl/6J mice. E12.5 pancreatic anlagen were relatively undifferentiated except for the presence of condensing tubuloacinar cords. By 2 weeks after implantation, pancreatic anlagen transplanted into rats had enlarged and differentiated such that islets of Langerhans that stained positive for insulin could be delineated. Continued differentiation, as reflected by the presence of "ductal" islets connected to the duct epithelium, was observed at 6 weeks after implantation. At 15 weeks after implantation, "mature" islets had separated from the ducts. Electron microscopy showed eccentric dense bodies within clear vacuoles consistent with insulin granules. Little or no acinar tissue was present in developed anlagen. Within 5 weeks of pancreatic anlagen transplantation, levels of glucose in rats rendered diabetic by an injection of streptozotocin were normalized compared with levels in nontransplanted diabetic controls. Rat pancreatic anlagen underwent growth and development in the peritoneum of C57Bl/61 mice that received costimulatory blocking agents but not in the absence of costimulatory blockade. We concluded that whole E12.5 pancreatic anlagen undergo growth, differentiation, and function after intraperitoneal placement. Implantation of the embryonic pancreas, a "cellular" transplant, is followed by selective differentiation of islet compared with acinar components.