Effects of Short-Term Exposure of Leuciscus rutilus L. (Pisces) to Phenylmercuric Hydroxide

The effects of phenylmercuric hydroxide (PMOH) on Leuciscus rutilus L. (Pisces) was studied after the acute exposure of fishes to a concentration of 1.0 mg/i (0.3 x 10-5 M). 1. The respiration of isolated gill filaments was inhibited by about 30 per cent. The cause of this inhibition was chiefly the damage to the secondary lamellae. 2. When the oxygen content of blood drawn from the fishes was measured, a pronounced decrease (82 per cent) was obtained, compared with that of blood drawn from untreated specimens. 3. The haemolytic effect of PMOH on fish erythrocytes was studied in vitro. The half-haemolysis time was 55 min. at a concentration of 0.5 x 10-4 M. No degree of haemolysis had occurred in blood drawn from poisoned fishes. 4. A small inhibition (9 per cent) was found in the oxygen consumption of brain slices from animals exposed to PMOH. 5. The oxygen uptake of both liver slices and liver mitochondria from exposed animals increased by 15 and 20 per cent respectively while glycolysis was inhibited by about 20-25 per cent.