Ruthenium red-induced loss of matrix K+ from uncoupled heart mitochondria

Ruthenium red induces the loss of endogenous K⁺ from isolated beef heart mitochondria treated with an uncoupler. This induction of K⁺ loss occurs at the same ruthenium red titer as the inhibition of the Ca²⁺-uniporter. This raises the possibility that ruthenium red may alter the Ca²⁺-uniporter in such a way as to produce a K⁺-conducting channel.     

A comparison of Antarctic euphausiids sampled by net and from geothermally heated waters: insights into sampling bias

The Antarctic euphausiids Euphausia superba and E. crystallorophias were sampled using an 8 m² rectangular midwater trawl inside the caldera of Deception Island. Specimens of the same species were collected on the same day from the strandline and sublittoral fringe within the caldera at a bay where these euphausiids had been incapacitated by high temperature geothermally heated waters. Differences between length frequency distributions of samples obtained by both methods were investigated once net-caught specimens had been subject to the simulated effects of geothermally heated waters. Differences between maturity stage/sex ratios for E. superba samples were also assessed. No significant differences between sizes of net-caught or beach-sampled E. crystallorophias were detected, but significant differences were found between both the sizes and sex/maturity stages for E. superba samples. Possible explanations for these differences are discussed. Accepted: 15 March 1999