scholarly journals Interleukin-1? effects on cyclic GMP and cyclic AMP in cultured rat islets of Langerhans ? arginine ? dependence and relationship to insulin secretion

Diabetologia ◽  
1993 ◽  
Vol 36 (1) ◽  
pp. 9-16 ◽  
Author(s):  
I. C. Green ◽  
C. A. Delaney ◽  
J. M. Cunningham ◽  
V. Karmiris ◽  
C. Southern
Keyword(s):  
Insulin Secretion ◽  
Cyclic Amp ◽  
Islets Of Langerhans ◽  
Cyclic Gmp ◽  
Interleukin 1 ◽  
Rat Islets ◽  
Rat Islets Of Langerhans

Interleukin 1 is Potent Modulator of Insulin Secretion from Isolated Rat Islets of Langerhans

Diabetes ◽  
1987 ◽  
Vol 36 (8) ◽  
pp. 963-970 ◽  
Author(s):  
P. G. Comens ◽  
B. A. Wolf ◽  
E. R. Unanue ◽  
P. E. Lacy ◽  
M. L. McDaniel
Keyword(s):  
Insulin Secretion ◽  
Islets Of Langerhans ◽  
Interleukin 1 ◽  
Rat Islets ◽  
Isolated Rat Islets ◽  
Rat Islets Of Langerhans ◽  
Isolated Rat

Interleukin 1 is potent modulator of insulin secretion from isolated rat islets of Langerhans

Diabetes ◽  
1987 ◽  
Vol 36 (8) ◽  
pp. 963-970 ◽  
Author(s):  
P. G. Comens ◽  
B. A. Wolf ◽  
E. R. Unanue ◽  
P. E. Lacy ◽  
M. L. McDaniel
Keyword(s):  
Insulin Secretion ◽  
Islets Of Langerhans ◽  
Interleukin 1 ◽  
Rat Islets ◽  
Isolated Rat Islets ◽  
Rat Islets Of Langerhans ◽  
Isolated Rat

scholarly journals Inhibition of insulin secretion from rat islets of Langerhans by interleukin-6. An effect distinct from that of interleukin-1

1990 ◽  
Vol 272 (1) ◽  
pp. 243-245 ◽  
Author(s):  
C Southern ◽  
D Schulster ◽  
I C Green
Keyword(s):  
Insulin Secretion ◽  
Islets Of Langerhans ◽  
Interleukin 6 ◽  
Interleukin 1 ◽  
Inhibitory Effect ◽  
Tnf Alpha ◽  
Necrosis Factor Alpha ◽  
Rat Islets ◽  
Factor Alpha ◽  
Rat Islets Of Langerhans

Glucose-induced insulin secretion from islets cultured in the presence of interleukin-6 (IL-6) for 12-24 h was inhibited to a similar extent as when islets were treated with interleukin-1 beta (IL-1 beta). However, unlike IL-1 beta, IL-6 did not potentiate insulin secretion during an acute (30 min) exposure of islets to the cytokine, nor did it inhibit DNA synthesis during a 24 h culture period. A 12 h pretreatment of islets with tumour necrosis factor-alpha (TNF-alpha) combined with IL-1 beta potentiated the inhibitory effect of IL-1 beta on secretion, such that 20 mM-glucose-induced insulin secretion was abolished. No synergistic inhibition of secretion was observed with TNF-alpha and IL-6. However, IL-1 beta and IL-6 were found to inhibit insulin secretion in an additive manner. These results suggest that IL-6 inhibits insulin secretion in a manner distinct from that of IL-1 beta, and that IL-6 is unlikely to mediate the inhibitory effects of IL-1 beta or TNF-alpha on rat islets of Langerhans.

scholarly journals Stimulation of Adenylate Cyclase by Ca2+ and Calmodulin in Rat Islets of Langerhans: Explanation for the Glucose-induced Increase in Cyclic AMP Levels

Diabetes ◽  
1980 ◽  
Vol 29 (1) ◽  
pp. 74-77 ◽  
Author(s):  
G. W. G. Sharp ◽  
D. E. Wiedenkeller ◽  
D. Kaelin ◽  
E. G. Siegel ◽  
C. B. Wollheim
Keyword(s):  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
Islets Of Langerhans ◽  
Rat Islets ◽  
Rat Islets Of Langerhans ◽  
Stimulation Of

Immunoprecipitation of a pertussis toxin substrate of the Go family from rat islets of Langerhans

1992 ◽  
Vol 12 (2) ◽  
pp. 95-100 ◽  
Author(s):  
Nicholas S. Berrow ◽  
Roger D. Hurst ◽  
Susan L. F. Chan ◽  
Noel G. Morgan
Keyword(s):  
Molecular Weight ◽  
Insulin Secretion ◽  
Adenylate Cyclase ◽  
G Protein ◽  
G Proteins ◽  
Islets Of Langerhans ◽  
Pertussis Toxin ◽  
Inhibitory Receptors ◽  
Rat Islets ◽  
Rat Islets Of Langerhans

Rat islets express a pertussis toxin sensitive G-protein involved in receptor-mediated inhibition of insulin secretion. This has been assumed previously to represent “Gi” which couples inhibitory receptors to adenylate cyclase. Incubation of islet G-proteins with32P-NAD and pertussis toxin resulted in the labelling of a band of molecular weight 40,000. This band was very broad and did not allow resolution of individual components. Incubation of the radiolabelled proteins with an anti-Go antiserum resulted in specific immunoprecipitation of a32P-labelled band. These results demonstrate that the complement of pertussis toxin sensitive G-proteins in rat islets includes Go.

Calcium distribution in islets of Langerhans: a study of calcium concentrations and of calcium accumulation in B cell organelles

1975 ◽  
Vol 19 (2) ◽  
pp. 395-409
Author(s):  
S.L. Howell ◽  
W. Montague ◽  
M. Tyhurst
Keyword(s):  
Endoplasmic Reticulum ◽  
Cyclic Amp ◽  
B Cell ◽  
Islets Of Langerhans ◽  
Cyclic Gmp ◽  
Cell Organelles ◽  
Calcium Accumulation ◽  
Labile Pool ◽  
Storage Granules ◽  
Rat Islets Of Langerhans

Calcium concentrations of various pancreatic B cell organelles have been determined by X-ray microanalysis of areas of frozen sections of unfixed rat islets of Langerhans. Highest concentrations were detected in storage granules and in mitochondria, although calcium was also present in nuclei, in areas of endoplasmic reticulum and of cytoplasm. Accumulation of 45Ca by isolated organelles has been studied in homogenates and isolated subcellular fractions of rat islets of Langerhans. In the presence of a permeant anion (oxalate or phosphate), accumulation of 45Ca into mitochondria and microsomes was strongly stimulated by ATP. This net uptake was diminished during incubation of homogenates or of a mitochondria plus storage granule-rich fraction in the presence of cyclic AMP, dibutyryl cyclic GMP; 2:4-dinitrophenol or of ruthenium red. Investigations of the characteristics of 45Ca accumulation by homogenates prepared from storage granule-depleted islets showed no differences from those of normal islets, suggesting that the granules do not represent an important labile pool of calcium. With the exception of cyclic AMP and cyclic GMP none of the insulin secretagogues tested (glucose, leucine, arginine, adrenalin, noradrenalin, theophylline, glibenclamide) altered calcium accumulation by islet homogenates. On the basis of absolute calcium levels and of 45Ca uptake studies it is concluded that islet B cells contain a readily exchangeable mitochondrial calcium pool, and an endoplasmic reticulum pool containing a lower concentration of calcium which is also readily exchangeable. The storage granules, despite their high calcium content, do not appear to constitute a labile pool. It seems likely that the labile mitochondria and endoplasmic reticulum pools play a predominant role in the regulation of cytoplasmic free calcium levels, which may in turn be important in the regulation of rates of insulin secretion.

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