[Effect of liposomes containing antibodies to cyclic nucleotide phosphodiesterase on the receptor potential of rods and cones of the frog retina].

Liposomes loaded with monospecific cGMP-phosphodiesterase (PDE) antibodies act like PDE inhibitors (methylxantins, papaverine) on the aspartate-isolated rod and cone receptor potentials of the isolated perfused rod retina. The response amplitude drastically increases, especially at low stimulus strength, and its time course slows down. Pure lipid liposomes with no antibodies, liposomes loaded with control immunoglobulins, as well as PDE antibodies without liposomes, have no such actions. The effects are readily reversible by wash-out, which implies the liposome + antibodies action without penetrating the cells. The increase in the response amplitude can be only partly explained by the measured increase in the extracellular resistance of the photoreceptor layer under liposome action. It is supposed that the specific adsorption of liposomes on the photoreceptor cell surface changes the function of the intracellular transmission mechanism or (and) the properties of ionic channels of the plasma membrane in yet unknown way.