The effect of copper ions on the lipid composition of subcellular membranes in Hydrilla verticillata.

The paper studies changes in the content and composition of lipids in the membranes of chloroplasts, mitochondria and microsomes of the aquatic plant Hydrilla verticillata exposed to copper ions (100 μM; 1, 3, 6 and 24 h). The rate of copper accumulation and the coefficient of its extraction by the plant were also determined. The presence of copper in the incubation medium and its accumulation in the plant tissues decreased the content of photosynthetic pigments, stimulated lipid peroxidation and enhanced membrane permeability.

Influence of serotonin on calcium transport in rat liver mitochondria.

It was shown in experiments in vitro that serotonin, depending on the concentration, has different effects on calcium transport in rat liver mitochondria. In a concentration of 10(-6) M it increases the ability of the mitochondria to bind calcium; in a higher concentration (10(-4) M) serotonin accelerates the release of calcium from the mitochondria. The effect of serotonin is detected at a calcium concentration in sucrose medium of the order of 10(-4) M and is not observed when the mitochondria are incubated in a complete reaction medium.