Protective action of methylglyoxal bis (guanylhydrazone) on the mitochondrial membrane.
At low concentrations (0.5-1.0 mM) methylglyoxal bis (guanylhydrazone) (MGBG) exhibited a clearcut protection of rat liver mitochondria against the deenergizing action of either Ca2+, or oxidizing agents (butylhydroperoxide and oxaloacetate). Such a protection resulted from the prevention of transmembrane potential decay, discharge of accumulated Ca2+, release of mitochondrial Mg2+, adenine nucleotides and pyridine nucleotides and mitochondrial swelling. At high concentrations (5-10 mM) MGBG induced functional alterations of mitochondria (decrease of transmembrane potential, lower capability to accumulate and to retain Ca2+) which can be reversed by resuspension of mitochondria in a MGBG free medium. These reversible mitochondrial alterations by high MGBG concentrations are interpreted as a consequence of an aggregation and coprecipitation of suspended mitochondria.
Centro per lo Studio della Fisiologia Mitocondriale CNR, Università di Padova, Italy.
A
A
Toninello
D
D
Siliprandi
P
P
Castagnini
M C
MC
Novello
N
N
Siliprandi
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002449:Cell Aggregation / Q000187:drug effects; D002462:Cell Membrane / Q000187:drug effects; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects* / Q000502:physiology; D008935:Mitoguazone / Q000494:pharmacology*; D051381:Rats
D000255:Adenosine Triphosphate; D008935:Mitoguazone; D002118:Calcium