Secretagogues cause a preferential discharge of large size granules in rat pancreas

1984 ◽  
Vol 62 (12) ◽  
pp. 1288-1292 ◽  
Author(s):  
Adrien R. Beaudoin ◽  
Gilles Grondin ◽  
Mario Filion ◽  
André Lord
Keyword(s):  
Sample Size ◽  
Exocrine Pancreas ◽  
Distribution Curve ◽  
Granule Size ◽  
Size Reduction ◽  
Zymogen Granules ◽  
Rat Pancreas ◽  
Large Size ◽  
Granule Diameter

We have compared the diameters of zymogen granules in the exocrine pancreas of fasted or stimulated rats. The average granule diameter was 0.73 μm ± 0.18 SD (sample size, 1460) in fasted animals and significantly reduced to 0.68 μm ± 0.17 SD (sample size, 860) after 120 min and two intraperitoneal injections of urecholine. Reduction of granule size was attributable to the preferential discharge of large size granules. The range between first and third quartiles of the distribution curve was identical in the two groups at 0.24 μm. There was no significant increase in the proportion of granules smaller than 0.40 μm after urecholine stimulation. A third group of animals was "hyperstimulated" by an infusion of a mixture of caerulein, secretin, and urecholine. After 210 min, the average granule diameter was reduced to 0.43 μm ± 0.14 SD (sample size, 786). The range between first and third quartiles of the distribution curve was 0.16 μm. In this group, 43.5% of the granules was smaller than 0.40 μm. Granule size reduction was accompanied by the appearance of numerous pleiomorphic condensing vacuoles. The present results strongly support the views that secretagogues cause the preferential release of large size granules and favor the formation of small size granules.

scholarly journals Multivariate Fire Risk Models Using Sample-Size Reduction and Copula Regression in Kalimantan, Indonesia

2021 ◽  
Author(s):  
Mohamad Khoirun Najib ◽  
Sri Nurdiati ◽  
Ardhasena Sopaheluwakan
Keyword(s):  
Regression Model ◽  
Sample Size ◽  
Joint Distribution ◽  
El Nino ◽  
Fire Risk ◽  
Size Reduction ◽  
Total Precipitation ◽  
Climate Conditions ◽  
Dry Spells ◽  
Sample Size Reduction

Abstract The copula-based joint distribution can construct a fire risk model to improve forest fires' early warning system, especially in Kalimantan. In this study, we model and analyze the copula-based joint distribution between climate conditions and hotspots. We used several climate conditions, such as total precipitation, dry spells, and El Nino-Southern Oscillation (ENSO). We used copula functions with sample size reduction to construct the joint distributions and the copula regression model to estimate the fire size. The results show that the probability of extreme hotspots number during normal ENSO conditions is very rare and almost near zero during La Nina. Other than that, extreme hotspot event (more severe than in 2019) during El Nino is more sensitive to total precipitation than dry spells based on the conditional survival function. However, the copula regression model found that the model used dry spells as a climate condition better than total precipitation. In this model, the 95% confidence interval of the expected hotspots can cover all actual hotspots data.

A Study of the Fixation of the Granular Elements in Rat Pancreas

1962 ◽  
Vol s3-103 (64) ◽  
pp. 451-456
Author(s):  
C. LEVENE ◽  
P. FENG
Keyword(s):  
Acetic Acid ◽  
Potassium Dichromate ◽  
Zymogen Granules ◽  
Paraffin Sections ◽  
Rat Pancreas ◽  
Aldehyde Fuchsin

Rat pancreases were fixed in 6 primary fixatives and 16 fixative mixtures. Paraffin sections were stained for α and zymogen granules with chromalum/haematoxylin/phloxine, and for β granules with aldehyde-fuchsin. Fixation of α and β granules was obtained with all fixatives containing formaldehyde or potassium dichromate. Zymogen granules were only fixed by fixatives containing formaldehyde, and then only if acetic acid was omitted. Formaldehyde alone was adequate for fixation of α, β, and zymogen granules. For fixation of α and β granules only, the mixture of formaldehyde and acetic acid was preferable because the sections were technically better.

Serglycin proteoglycan is not implicated in localizing exocrine pancreas enzymes to zymogen granules

2009 ◽  
Vol 88 (8) ◽  
pp. 473-479 ◽  
Author(s):  
Carsten U. Niemann ◽  
Jack B. Cowland ◽  
Elisabeth Ralfkiaer ◽  
Magnus Åbrink ◽  
Gunnar Pejler ◽  
...  
Keyword(s):  
Exocrine Pancreas ◽  
Zymogen Granules

On biometric data sample size reduction when using Bayesian multidimensional correlation function

2017 ◽  
Vol 15 (2) ◽  
Author(s):  
A.I. Ivanov ◽  
◽  
P.S. Lozhnikov ◽  
A.E. Sulavko ◽  
Y.I. Serikova ◽  
...  
Keyword(s):  
Correlation Function ◽  
Sample Size ◽  
Size Reduction ◽  
Biometric Data ◽  
Sample Size Reduction

scholarly journals CHANGES IN PANCREATIC ACINAR CELLS DURING PROTEIN DEPRIVATION

1962 ◽  
Vol 12 (2) ◽  
pp. 313-327 ◽  
Author(s):  
Bernard Weisblum ◽  
Lawrence Herman ◽  
Patrick J. Fitzgerald
Keyword(s):  
Golgi Apparatus ◽  
Nuclear Matrix ◽  
Pancreatic Enzyme ◽  
Acinar Cells ◽  
Normal Structure ◽  
Pancreatic Acinar Cells ◽  
Zymogen Granules ◽  
Protein Deprivation ◽  
Rat Pancreas ◽  
Protein Free Diet

After 10 days of a protein-free diet the acinar cells of the rat pancreas showed a coarsening of nuclear matrix, depletion of zymogen granules, some loss of ribosomes, and a widening of the spaces between ergastoplasmic membranes. In addition, there could be found, but rarely, a lesion of the ergastoplasm consisting of vacuoles of agranular, disoriented membranes, which was similar to a lesion produced by ethionine. Thereafter, a return toward normal structure occurred which was characterized by beginning increase in the size of the Golgi apparatus at 12 days, appearance of zymogen granules at 18 days, and a relatively normal appearing but smaller cell at 28 days. After 10 to 12 days of protein deprivation a reversal of many of the morphologic effects of protein deprivation was accompanied by a return toward normal of some pancreatic enzyme activities. Possibly this spontaneous return toward normal levels represented a raiding of protein stores, or it may have been an adaptive phenomenon.

Nonparallel secretion of GP-2 from exocrine pancreas implies luminal coupling between acinar and duct cells

1994 ◽  
Vol 267 (1) ◽  
pp. G40-G51 ◽  
Author(s):  
S. D. Freedman ◽  
K. Sakamoto ◽  
G. A. Scheele
Keyword(s):  
Exocrine Pancreas ◽  
Acinar Cells ◽  
Zymogen Granule ◽  
Zymogen Granules ◽  
Pancreatic Acini ◽  
Glycosyl Phosphatidylinositol ◽  
Cellular Processes ◽  
Rat Exocrine Pancreas

The in vivo and in vitro secretion of glycoprotein-2 (GP-2), a glycosyl phosphatidylinositol (GPI)-anchored protein from the rat exocrine pancreas, was characterized. GP-2 was secreted in a nonparallel manner compared with amylase, a marker of secretory enzymes. Attenuated GP-2 secretion correlated with hormones that stimulated exocytosis in acinar cells. Augmented GP-2 secretion correlated with hormones that stimulated fluid and bicarbonate secretion from ductal elements. Immunofluorescence studies identified an enriched pool of GP-2 tightly bound to the apical membranes of acinar cells in addition to zymogen granules. This non-zymogen granule pool appears to represent the source of GP-2 released from acinar cells in a nonparallel manner. With the use of dispersed pancreatic acini largely devoid of ductal elements, GP-2 release was found to be augmented by alkaline pH. Thus GP-2 secretion appears to be modulated by two discrete cellular processes: 1) delivery of prereleased GP-2 within zymogen granules to the ductal lumen by exocytic mechanisms and 2) enzymatic release of GPI-anchored GP-2 from the luminal membranes, a kinetic process that appears to be regulated by secretin- or carbachol-induced secretion of bicarbonate.

An Electron Microscopical Study of Neutral Red Granules in Mouse Exocrine Pancreas

1964 ◽  
Vol s3-105 (70) ◽  
pp. 219-226
Author(s):  
JENNIFER M. BYRNE
Keyword(s):  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Golgi Apparatus ◽  
Normal Tissue ◽  
Exocrine Pancreas ◽  
Ultrastructural Level ◽  
Neutral Red ◽  
Microscopical Study ◽  
Zymogen Granules ◽  
Electron Microscopical

The neutral red granule cycle in the mouse exocrine pancreas was studied with the electron microscope in order to discover what changes appear at an ultrastructural level in cells treated with neutral red. There are no changes in the endoplasmic reticulum, the nucleus, the Golgi apparatus, the zymogen granules, or the mitochondria of stained cells when compared with normal tissue. Osmiophil inclusions are found which in their size and distribution correspond to the neutral red granules seen under the light microscope. Such inclusions are not seen in normal tissue. They resemble morphologically the lysosomes of various tissues.

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