Effect of falloidin on permeability of intercellular channels for inorganic ions and fluorescein

It has been shown on larva gland that falloidin - a toxic of toadstool inducing an increased number of membrane microfilaments-affects the efficiency of intercellular transfer of small inorganic ions and molecules of organic dye fluorescein-Na. The data obtained are in favour of the participation of microfilaments in the regulation of intercellular diffusion communication.     

Study of the role of microtubules in the regulation of activity of highly permeable contact membranes

It was shown that various antitubulines-colchicin (10(-4) M), vinblastin-sulfate (10(-5) M) and vinoristin-sulfate (10(-5) M) do not affect the intercellular diffusion exchange of small inorganic ions and organic dye fluorescein in Drosophila virilis larva salivari gland. It is suggested that microtubules do not take part in functional activity regulation of gap junction high-permeable membranes.     

Effect of the critical fragmentation of erythrocyte membranes]

After sonification of erythrocyte membranes, some changes were registered in these including a loss of their ability to structural rearrangements caused by cAMP (ESR-spectroscopy and luminescence data), an increase in cAMP binding and aggregation of intramembrane particles (freeze-fracture data). These findings suggest a non-identity of the structural organization in membranes and in their fragments. The cooperative nature of membrane structural modification at ultrasonic fragmentation is shown.     

IGFBP-4 Proteolysis by PAPP-A in a Primary Culture of Rat Neonatal Cardiomyocytes under Normal and Hypertrophic Conditions

Biochemistry (Moscow) - Cardiovascular diseases (CVD) are among the leading causes of death and disability worldwide. Pregnancy-associated plasma protein-A (PAPP-A) is a matrix metalloprotease...     

Effect of Fe2+- and gamma-induced lipid peroxidation on respiration and oxidative phosphorylation in the mitochondria

Lipid peroxidation activated by low concentrations of Fe2+ ions in a medium (1-5 microM) and gamma-quanta (10-50 Gy) stimulates the oxygen consumption and oxidative phosphorylation during the initial period of incubation (10-20 min). With relatively high concentrations of Fe2+ ions and higher radiation doses (50-100 Gy) inhibition of the activity of mitochondria is registered with respect to both indices.     

Effect of the state of the lipid phase of the membrane on the effectiveness of photochemical modification of erythrocyte acetylcholinesterase

Modification of the lipid phase structure of the erythrocyte membrane by phospholipases A2, C and D as well as the partial depletion of cholesterol was shown to be accompanied by the change of the acetylcholinesterase (AChE) UV-sensitivity. The ability of UV-light to change the catalytic properties (Km) of the membrane-bound AChE not observed for free AChE (constant value of Km) and known as the phenomenon of photochemical allotopy, is retained in the cholesterol depleted membranes and disappears after an enzymatic treatment of the membranes by phospholipases. The possible non-photochemical influence of the membrane lipid phase in response to UV-damage of membrane-bound AChE is discussed.