Sodium transport inhibition by selective mitochondrial inhibitors in the urinary bladder of the toad

✍ Scribed by Cecilia Hidalgo; Mitzy Canessa-Fischer

• Publisher: John Wiley and Sons
• Year: 1966
• Tongue: English
• Weight: 759 KB
• Volume: 68
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.1040680213

✦ Synopsis

The effects of selective mitochondrial inhibitors on the short-circuit current and oxygen consumption displayed by the isolated urinary bladder of the toad was studied.

Three types of compounds were used: ( a ) electron transfer inhibitors, Amytal, Cyanide and Antimycin A; ( b ) energy transfer inhibitors Guanidine, Oligomycin and Rutamycin; and ( c ) uncoupling agents, Carbonyl cyanide m-chlorophenylhydrazone and 2-4 dinitrophenol.

The kinetics of inhibition of oxygen consumption indicated that the inhibitors tested were effectively reaching the mitochondria of the bladder cells.

Different kinetics of inhibition of short-circuit current were obtained with the various inhibitors tested.

Uncouplers and electron transfer inhibitors rapidly blocked the short-circuit current; energy transfer inhibitors only produced a slow and partial inhibition.

A site of energy-coupling, tentatively identified with the intermediate formed in the energy transfer reactions closest to the electron transfer chain, is proposed.