Glucagon effects on the membrane potential and calcium uptake rate of rat liver mitochondria.

Wingrove DE, Amatruda JM, Gunter TE

The Journal of biological chemistry1 Aug 1984Cited by 59 (Europe PMC)

PMID6204980DOI10.1016/s0021-9258(17)42713-xPepBankPUB-06204980

Publisher page PubMedAsk about this study

Summary

It has been widely reported that the in vivo administration of glucagon to rats results in the stimulation of calcium influx in subsequently isolated liver mitochondria. The mechanism of this effect is investigated through simultaneous measurements of calcium uptake rate and mitochondrial membrane potential. This allows the measurement of the calcium uniporter conductance independent of hormonal effects on electron transport or respiration. Two experimental approaches are used. The first involves measuring the uptake of 40-50 nmol of Ca2+/mg of mitochondrial protein with the calcium dye antipyrylazo III; the second uses 45Ca2+ to follow uptake in the presence of 0.5 to 1.5 microM free calcium, buffered with HEDTA. In both cases a tetraphenyl phosphonium electrode is used to follow membrane potential, and membrane potential is varied using either malonate or butylmalonate in the presence of rotenone. The relative merits of these two approaches are discussed. The conductance of the calcium uniporter is found not to be stimulated by glucagon pretreatment. Also, the relative glucagon stimulation of both calcium influx and membrane potential is found to increase with increasing malonate concentration. These results imply that there is no direct stimulation of calcium uptake into liver mitochondria following glucagon treatment. The results are consistent with a glucagon stimulation of substrate transport, substrate oxidation, or a stimulation of electron transport resulting in an increased membrane potential and secondary stimulation of calcium uptake.

CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study3

3 results from studies that gave the peptide. No result from this study comes from people.

01AnimalAnimal study (in vivo)Mechanism
In rats, glucagon pretreatment did not stimulate the conductance of the liver mitochondrial calcium uniporter.
In plain wordsIn rats, glucagon pretreatment did not increase conductance through the liver mitochondrial calcium entry pathway.
Peptide
Glucagon
Outcome
No significant changeCalcium uniporter conductance
Study
ratn: not reported in source
Liver mitochondria isolated after in vivo glucagon pretreatment
Outcome group
Mitochondrial function · Liver
Studied dose
Dose not stated
Source sentences
Summary
The conductance of the calcium uniporter is found not to be stimulated by glucagon pretreatment.
2 context sentences(design, population, supporting numbers)
Summary · context
It has been widely reported that the in vivo administration of glucagon to rats results in the stimulation of calcium influx in subsequently isolated liver mitochondria.
Summary · context
The mechanism of this effect is investigated through simultaneous measurements of calcium uptake rate and mitochondrial membrane potential.
Show in the study text Report a problemFND-0620498001
02AnimalAnimal study (in vivo)Mechanism
In rats' isolated liver mitochondria, relative glucagon stimulation of calcium influx increased with malonate concentration.
In plain wordsIn rats, liver mitochondrial calcium influx stimulation after glucagon increased as malonate concentration increased.
Peptide
Glucagon
Outcome
IncreaseCalcium influx dependence on malonate
Study
ratn: not reported in source
Liver mitochondria isolated after in vivo glucagon pretreatment
Outcome group
Mitochondrial function · Liver
Studied dose
Dose not stated
Source sentences
Summary
Also, the relative glucagon stimulation of both calcium influx and membrane potential is found to increase with increasing malonate concentration.
2 context sentences(design, population, supporting numbers)
Summary · context
It has been widely reported that the in vivo administration of glucagon to rats results in the stimulation of calcium influx in subsequently isolated liver mitochondria.
Summary · context
The mechanism of this effect is investigated through simultaneous measurements of calcium uptake rate and mitochondrial membrane potential.
Show in the study text Report a problemFND-0620498002
03AnimalAnimal study (in vivo)Mechanism
In rats' isolated liver mitochondria, relative glucagon stimulation of membrane potential increased with malonate concentration.
In plain wordsIn rats, liver mitochondrial membrane potential stimulation after glucagon increased as malonate concentration increased.
Peptide
Glucagon
Outcome
IncreaseMembrane potential dependence on malonate
Study
ratn: not reported in source
Liver mitochondria isolated after in vivo glucagon pretreatment
Outcome group
Mitochondrial function · Liver
Studied dose
Dose not stated
Source sentences
Summary
Also, the relative glucagon stimulation of both calcium influx and membrane potential is found to increase with increasing malonate concentration.
2 context sentences(design, population, supporting numbers)
Summary · context
It has been widely reported that the in vivo administration of glucagon to rats results in the stimulation of calcium influx in subsequently isolated liver mitochondria.
Summary · context
The mechanism of this effect is investigated through simultaneous measurements of calcium uptake rate and mitochondrial membrane potential.
Show in the study text Report a problemFND-0620498003

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Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

Version 2Current
28 Oct 2026, 02:03 UTC
Study results updated
Version 1
27 Oct 2026, 16:35 UTC
First added · source update from Europe PMC

Subjects

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