scholarly journals Cellular distribution and amount of chromogranin A in bovine endocrine pancreas.

1988 ◽  
Vol 36 (5) ◽  
pp. 467-472 ◽  
Author(s):  
M Ehrhart ◽  
A Jörns ◽  
D Grube ◽  
M Gratzl
Keyword(s):  
Chromogranin A ◽  
Endocrine Cells ◽  
Endocrine Pancreas ◽  
Molar Ratio ◽  
Computer Assisted ◽  
Cellular Distribution ◽  
Tissue Extracts ◽  
Wet Weight ◽  
Pancreatic B Cells ◽  
Bovine Pancreas

We determined the cellular distribution and the amount of chromogranin A in endocrine cells of bovine pancreas using a polyclonal antibody against bovine adrenomedullary chromogranin A. The relative amounts of chromogranin A in the different cells of the endocrine pancreas were determined by computer-assisted analyses of the optical densities of the immunoreactivities in the stained sections. More than 80% of the immunoreactive chromogranin A was located in the pancreatic B-cells. In immunoblots of acid tissue extracts, only one chromogranin A band (MW 74 KD) was observed. Quantification of the immunoblots revealed that 3 micrograms of chromogranin A and 918 micrograms of insulin were present per gram pancreas (wet weight), equivalent to a molar ratio of 460 mumol chromogranin A per mol insulin.

scholarly journals Heterogeneity of chromogranin A-derived peptides in bovine gut, pancreas and adrenal medulla

1991 ◽  
Vol 276 (2) ◽  
pp. 471-479 ◽  
Author(s):  
A Watkinson ◽  
A C Jönsson ◽  
M Davison ◽  
J Young ◽  
C M Lee ◽  
...  
Keyword(s):  
Endocrine Cell ◽  
Cell Biology ◽  
Chromogranin A ◽  
Endocrine Cells ◽  
Cell Types ◽  
Intact Protein ◽  
Pancreatic Endocrine Cells ◽  
Gastric Corpus ◽  
Adrenal Chromaffin ◽  
Bovine Pancreas

Chromogranin A is produced in many endocrine cell types, and is widely used as a marker in endocrine-cell pathology and secretory-cell biology. There is some evidence that it may be proteolytically processed to yield the putative pancreatic regulatory peptide, pancreastatin, and, in order to characterize the relevant pathways in gastrointestinal and pancreatic endocrine cells, we have used, in radioimmunoassay, site-directed antibodies to pancreastatin itself (L331) and to a sequence of chromogranin A immediately C-terminal to pancreastatin (L300). The latter antibody revealed three major forms of immunoreactivity of 8 kDa and five peptides of approx. 3 kDa in bovine pancreas and gut extracts. The 8 kDa peptides were characterized as chromogranin A-(248-313)-peptides, i.e. C-terminally extended forms of pancreastatin; two of the 8 kDa variants differed in two positions, confirming a polymorphism predicted from cDNA sequencing. One of the 3 kDa peptides was characterized as chromogranin A-(297-313)-peptide, i.e. the C-terminal heptadecapeptide of the 8 kDa peptide that would be liberated after cleavage to yield pancreastatin. On the basis of chromatographic studies, immunohistochemistry and the stoichiometry of different immunoreactive peptides, three different pathways of chromogranin A processing were identified: in adrenal chromaffin cells chromogranin A existed mainly as the unmodified intact protein, in pancreatic islet and gastric antral endocrine cells pancreastatin and the 3 kDa peptides were major products, but in small intestine and gastric corpus endocrine cells there was little nor no pancreastatin and the 8 kDa cleavage product predominated. There are therefore important differences in the distribution of chromogranin A-derived peptides between quite closely related populations of endocrine cells that are attributable not only to variable post-translational cleavage but also to the expression of different primary sequences. It seems possible that in different cell types chromogranin A-derived peptides might subserve a variety of different functions.

scholarly journals The ontogeny of the endocrine pancreas in the fetal/newborn baboon

2012 ◽  
Vol 214 (3) ◽  
pp. 289-299 ◽  
Author(s):  
Amy R Quinn ◽  
Cynthia L Blanco ◽  
Carla Perego ◽  
Giovanna Finzi ◽  
Stefano La Rosa ◽  
...  
Keyword(s):  
Endocrine Cells ◽  
Endocrine Pancreas ◽  
Fold Increase ◽  
Pancreatic Tissue ◽  
Developmental Differences ◽  
Confocal Imaging ◽  
Cell Type ◽  
Pancreas Islet ◽  
Pancreas Weight

Erratic regulation of glucose metabolism including hyperglycemia is a common condition in premature infants and is associated with increased morbidity and mortality. The objective of this study was to examine histological and ultrastructural differences in the endocrine pancreas in fetal (throughout gestation) and neonatal baboons. Twelve fetal baboons were delivered at 125 days (d) gestational age (GA), 140d GA, or 175d GA. Eight animals were delivered at term (185d GA); half were fed for 5 days. Seventy-three nondiabetic adult baboons were used for comparison. Pancreatic tissue was studied using light microscopy, confocal imaging, and electron microscopy. The fetal and neonatal endocrine pancreas islet architecture became more organized as GA advanced. The percent areas of α-β-δ-cell type were similar within each fetal and newborn GA (NS) but were higher than the adults (P<0.05) regardless of GA. The ratio of β cells within the islet (whole and core) increased with gestation (P<0.01). Neonatal baboons, which survived for 5 days (feeding), had a 2.5-fold increase in pancreas weight compared with their counterparts killed at birth (P=0.01). Endocrine cells were also found in exocrine ductal and acinar cells in 125, 140 and 175d GA fetuses. Subpopulation of tissue that coexpressed trypsin and glucagon/insulin shows the presence of cells with mixed endo–exocrine lineage in fetuses. In summary, the fetal endocrine pancreas has no prevalence of a α-β-δ-cell type with larger endocrine cell percent areas than adults. Cells with mixed endocrine/exocrine phenotype occur during fetal development. Developmental differences may play a role in glucose homeostasis during the neonatal period and may have long-term implications.

scholarly journals Increased Chromogranin A–Positive Hormone-Negative Cells in Chronic Pancreatitis

2018 ◽  
Vol 103 (6) ◽  
pp. 2126-2135 ◽  
Author(s):  
Abu Saleh Md Moin ◽  
Megan Cory ◽  
Jennifer Choi ◽  
Allison Ong ◽  
Sangeeta Dhawan ◽  
...  
Keyword(s):  
Chronic Pancreatitis ◽  
Chromogranin A ◽  
Endocrine Cells ◽  
Acinar Cells ◽  
Pancreatic Acinar Cells ◽  
Cell Regeneration ◽  
Inflammation Marker ◽  
Β Cells ◽  
Cell Frequency ◽  
Endogenous Expression

Abstract Context Chronic pancreatitis (CP) is characterized by inflammation, fibrosis, and a loss of pancreatic acinar cells, which can result in exocrine and eventually endocrine deficiency. Pancreatitis has been reported to induce formation of new endocrine cells (neogenesis) in mice. Our recent data have implicated chromogranin A–positive hormone-negative (CPHN) cells as potential evidence of neogenesis in humans. Objective We sought to establish if CPHN cells were more abundant in CP in humans. Design, Setting, and Participants We investigated the frequency and distribution of CPHN cells and the expression of the chemokine C-X-C motif ligand 10 (CXCL10) and its receptor chemokine C-X-C motif receptor 3 in pancreas of nondiabetic subjects with CP. Results CPHN cell frequency in islets was increased sevenfold in CP [2.1% ± 0.67% vs 0.35% ± 0.09% CPHN cells in islets, CP vs nonpancreatitis (NP), P &lt; 0.01], as were the CPHN cells found as scattered cells in the exocrine areas (17.4 ± 2.9 vs 4.2 ± 0.6, CP vs NP, P &lt; 0.001). Polyhormonal endocrine cells were also increased in CP (2.7 ± 1.2 vs 0.1 ± 0.04, CP vs NP, % of polyhormonal cells of total endocrine cells, P &lt; 0.01), as was expression of CXCL10 in α and β cells. Conclusion There is increased islet endogenous expression of the inflammation marker CXCL10 in islets in the setting of nondiabetic CP and an increase in polyhormonal (insulin-glucagon expressing) cells. The increase in CPHN cells in CP, often in a lobular distribution, may indicate foci of attempted endocrine cell regeneration.

scholarly journals Three-dimensional structure of actin filaments and of an actin gel made with actin-binding protein.

1983 ◽  
Vol 96 (5) ◽  
pp. 1400-1413 ◽  
Author(s):  
R Niederman ◽  
P C Amrein ◽  
J Hartwig
Keyword(s):  
Actin Filaments ◽  
Binding Protein ◽  
Three Dimensional ◽  
Actin Binding ◽  
Dimensional Structure ◽  
Molar Ratio ◽  
Computer Assisted ◽  
Three Dimensional Structure ◽  
Actin Binding Protein ◽  
Critical Point Drying

Purified muscle actin and mixtures of actin and actin-binding protein were examined in the transmission electron microscope after fixation, critical point drying, and rotary shadowing. The three-dimensional structure of the protein assemblies was analyzed by a computer-assisted graphic analysis applicable to generalized filament networks. This analysis yielded information concerning the frequency of filament intersections, the filament length between these intersections, the angle at which filaments branch at these intersections, and the concentration of filaments within a defined volume. Purified actin at a concentration of 1 mg/ml assembled into a uniform mass of long filaments which overlap at random angles between 0 degrees and 90 degrees. Actin in the presence of macrophage actin-binding protein assembled into short, straight filaments, organized in a perpendicular branching network. The distance between branch points was inversely related to the molar ratio of actin-binding protein to actin. This distance was what would be predicted if actin filaments grew at right angles off of nucleation sites on the two ends of actin-binding protein dimers, and then annealed. The results suggest that actin in combination with actin-binding protein self-assembles to form a three-dimensional network resembling the peripheral cytoskeleton of motile cells.

Chromogranin: A newly recognized marker for endocrine cells of the human gastrointestinal tract

1985 ◽  
Vol 89 (6) ◽  
pp. 1366-1373 ◽  
Author(s):  
P. Facer ◽  
A.E. Bishop ◽  
R.V. Lloyd ◽  
B.S. Wilson ◽  
R.J. Hennessy ◽  
...  
Keyword(s):  
Gastrointestinal Tract ◽  
Chromogranin A ◽  
Endocrine Cells ◽  
Human Gastrointestinal Tract

Immunohistochemical localization of chromogranin A and B in the endocrine cells of the alimentary tract of the green frog, Rana esculenta

1994 ◽  
Vol 277 (2) ◽  
pp. 341-349 ◽  
Author(s):  
Loredana D'Este ◽  
Roberto Buffa ◽  
Micaela Pelagi ◽  
Antonio G. Siccardi ◽  
Tindaro Renda
Keyword(s):  
Chromogranin A ◽  
Endocrine Cells ◽  
Alimentary Tract ◽  
Rana Esculenta ◽  
Immunohistochemical Localization ◽  
Green Frog

Regional differences in catecholamine concentrations in bovine ovaries analysed by high-performance liquid chromatography

1991 ◽  
Vol 129 (2) ◽  
pp. 221-226 ◽  
Author(s):  
P. A. Denning-Kendall ◽  
M. L. Wild ◽  
Wathes D. C.
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Molar Ratio ◽  
Corpora Lutea ◽  
Wet Weight ◽  
High Concentrations ◽  
Highly Correlated ◽  
Very High

ABSTRACT Bovine corpora lutea and ovarian stroma were analysed by high-performance liquid chromatography for catecholamine content. High concentrations (up to 102 nmol/g wet weight) were found in both 'central' stroma, containing many blood vessels, and 'peripheral' stroma. Central stroma contained noradrenaline and some dopamine, whereas peripheral stroma contained a higher proportion of dopamine and also significant amounts of 3,4-dihydroxyphenylacetic acid (DOPAC). Occasional samples of stroma had very high amounts of dopamine, suggesting that it is stored in specific regions. Corpora lutea, although devoid of direct innervation, contained dopamine (up to 5·3 nmol/g) and noradrenaline (up to 1·2 nmol/g). The average dopamine: noradrenaline molar ratio was 1·19 : 1 and the concentrations of dopamine and noradrenaline were highly correlated (P < 0·002). The concentration of dopamine was significantly higher in the early luteal phase of the oestrous cycle than during the rest of the cycle or in pregnancy. The levels of noradrenaline and dopamine present in corpora lutea are sufficient to modulate the production of both oxytocin and progesterone by luteal cells in vitro. Journal of Endocrinology (1991) 129, 221–226

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