mersalyl and 6-6--dithiodinicotinic-acid

Topics: Adenosine Triphosphatases; Adenosine Triphosphate; Animals; Biological Transport, Active; Cholic Acids; Dinitrophenols; Disulfides; Glutamates; In Vitro Techniques; Kinetics; Mersalyl; Mitochondria; Mitochondria, Liver; Mitochondrial Swelling; Myocardium; Nicotinic Acids; Oligomycins; Oxidative Phosphorylation; Oxygen Consumption; Polarography; Proteins; Quaternary Ammonium Compounds; Rats; Sulfhydryl Reagents; Swine

CPDS (6,6'-dithiodinicotinic acid), a non permeant thiol agent which affects several mitochondrial functions in a way different to that of mersalyl [18-19] revealed striking differences between the phosphate translocating systems of pig heart and rat liver mitochondria. Pi entry was measured either by swelling in 0.12 M ammonium phosphate or by rapid centrifugation in 32Pi medium. Pi efflux was measured after preloading of mitochondria with 32Pi, by exchange against Pi or malate; the "ATP-FCCP" system has been tested previously [19]. In pig heart mitochondria, Pi entry seems to proceed exclusively via the Pi/OH- carrier; CPDS completely inhibits this transport and the energy-linked functions. In contrast n-butyl-malonate does not affect the Pi-entry and the energy-linked functions. The Pi efflux is not affected either by CPDS or mersalyl, which do not produce a swelling in the "ATP-uncoupler system". In rat liver mitochondria, CPDS inhibits only the Pi/OH- carrier; both CPDS and n-butylmalonate are necessary to inhibit completely Pi entry. CPDS as well as mersalyl provokes a swelling in the presence of the "APT-uncoupler system". The results suggest two distinct functions of phosphate transport in both types of mitochondria.

Topics: Animals; Biological Transport, Active; Calcium Chloride; Centrifugation; Disulfides; Glutamates; In Vitro Techniques; Kinetics; Malonates; Mersalyl; Mitochondria, Liver; Mitochondria, Muscle; Mitochondrial Swelling; Myocardium; Nicotinic Acids; Oligomycins; Oxidative Phosphorylation; Phosphates; Rats; Rotenone; Sulfhydryl Reagents; Swine