Modification of calcium retention capacity of rat liver mitochondria by phosphate and tert-butyl hydroperoxide

Title:

Modification of calcium retention capacity of rat liver mitochondria by phosphate and tert-butyl hydroperoxide

Creator:

Endlicher, R. , Drahota, Z., and Červinková, Z.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:296c8e2b-ec56-4b6c-a36f-4aebc34f1feb
uuid:296c8e2b-ec56-4b6c-a36f-4aebc34f1feb
doi:10.33549/physiolres.933912

Subject:

liver mitochondria, calcium retention capacity, mitochondrial permeability transition pore, phosphate, and tert-butyl hydroperoxide

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

By determining the calcium retention capacity (CRC) of rat liver mitochondria, we confirmed and extended previous observations describing the activation of mitochondrial swelling by phosphate and tert-butyl hydroperoxide (t-BHP). Using CRC measurements, we showed that both phosphate and t-BHP decrease the extent of calcium accumulation required for the full mitochondrial permeability transition pore (MPTP) opening to 35 % of control values and to only 15 % when both phosphate and t-BHP are present in the medium. When changes in fluorescence were evaluated at higher resolution, we observed that in the presence of cyclosporine A fluorescence values return after each Ca2+ addition to basal values obtained before the Ca2+ addition. This indicates that the MPTP remains closed. However, in the absence of cyclosporine A, the basal fluorescence after each Ca2+ addition continuously increased. This increase was potentiated both by phosphate and t-BHP until the moment when the concentration of intramitochondrial calcium required for the full opening of the MPTP was reached. We conclude that in the absence of cyclosporine A, the MPTP is slowly opened after each Ca2+ addition and that this rate of opening can be modified by various factors such as the composition of the media and the experimental protocol used.

Language:

English

Rights:

http://creativecommons.org/publicdomain/mark/1.0/
policy:public

Source:

Physiological research | 2019 Volume:68 | Number:1

Harvested from:

CDK

Metadata only:

false