Complete nucleotide sequence of a Coxsackievirus B-4 strain capable of establishing persistent infection in human pancreatic islet cells: Effects on insulin release, proinsulin synthesis, and cell morphology

2002 ◽  
Vol 68 (4) ◽  
pp. 544-557 ◽  
Author(s):  
Hong Yin ◽  
Anna-Karin Berg ◽  
Jan Westman ◽  
Claes Hellerström ◽  
Gun Frisk
1984 ◽  
Vol 218 (3) ◽  
pp. 887-892 ◽  
Author(s):  
P Lindström ◽  
J Sehlin

To characterize the effect of glucose on the intracellular pH (pHi) of pancreatic islet cells, we measured the accumulation of 14C-labelled 5,5-dimethyloxazolidine-2,4-dione ([14C]DMO) in beta-cell-rich islets from ob/ob mice. D-Glucose (20 mM) stimulated insulin release and enhanced the [14C]DMO equilibrium uptake corresponding to an increase of pHi by about 0.15 unit. The glucose effect on DMO uptake was concentration-dependent, with half-maximal effect at about 4 mM-glucose and maximum effect at about 10 mM-glucose. It was inhibited by 20 mM-mannoheptulose and potentiated by 4 mM-L-5-hydroxytryptophan, but not affected by 2 mM-theophylline. Mannoheptulose is an inhibitor and L-5-hydroxytryptophan and theophylline are potentiators of glucose-stimulated insulin release. The glucose-induced increase in pHi appeared rapidly (7 min) and persisted for at least 30 min and it was observed both in bicarbonate/CO2-buffered and in Hepes [4-(2-hydroxyethyl)-1-piperazine-ethanesulphonic acid]-buffered media. Addition of extracellular bicarbonate buffer lowered the pHi, but did not affect basal insulin release, whereas 5 mM-NH4+ increased pHi and induced a 4-fold increase of basal insulin release. We conclude that, in contrast with previous assumptions, glucose increases intracellular pH in the islet cells. This effect may be coupled to the glucose metabolism and associated with triggering of insulin release.


1984 ◽  
Vol 220 (2) ◽  
pp. 433-440 ◽  
Author(s):  
A Sener ◽  
F Malaisse-Lagae ◽  
S P Dufrane ◽  
W J Malaisse

NADP-linked isocitrate dehydrogenase and malic enzyme [malate dehydrogenase (decarboxylating) (NADP)] activities were characterized in the cytosol of pancreatic islet cells. D-Glucose and L-leucine augmented the cytosolic NADPH/NADP+ ratio, as judged from the isocitrate/2-oxoglutarate and malate/pyruvate islet contents. The flow rate through the malic enzyme was judged from the output of labelled pyruvate by islets exposed to either L-[U-14C]glutamine or L-[U-14C]leucine. The cytosolic generation of NADPH, e.g. at the level of the malic enzyme, may play a role in the coupling of metabolic to secretory events in the process of nutrient-stimulated insulin release.


Endocrinology ◽  
1982 ◽  
Vol 111 (1) ◽  
pp. 86-94 ◽  
Author(s):  
PHILIPPE A. HALBAN ◽  
CLAES B. WOLLHEIM ◽  
BENIGNA BLONDEL ◽  
PAOLO MEDA ◽  
ERIC N. NIESOR ◽  
...  

2007 ◽  
Vol 30 (4) ◽  
pp. 644-647 ◽  
Author(s):  
Takashi Tomita ◽  
Mariko Onishi ◽  
Eiji Sato ◽  
Yasuhiro Kimura ◽  
Kenji Kihira

1976 ◽  
Vol 366 (2-3) ◽  
pp. 185-188 ◽  
Author(s):  
Lars-�ke Idahl ◽  
�ke Lernmark ◽  
Janove Sehlin ◽  
Inge-Bert T�ljedal

Diabetes ◽  
1980 ◽  
Vol 29 (6) ◽  
pp. 497-500 ◽  
Author(s):  
P. Meda ◽  
E. L. Hooghe-Peters ◽  
L. Orci

Sign in / Sign up

Export Citation Format

Share Document