Neuroglial relationships in the crayfish stretch receptor under photodynamic injury: changes in the nuclear morphology

摘要

Sulphonated alumophthalocyanine Photosens AIPcS_n (mean n= 3.1) localizes predominately in the glial envelope surrounding the crayfish stretch receptor neuron. PDT treatment of the isolated stretch receptor organ with 10~(-7) M Photosens inhibits and then irreversibly abolishes neuron activity for approximately 20 min. Then, in 1.7 h after PDT treatment, the plasma membrane loses its integrity and propidium iodide enters into the cytosol and stains the nuclear chromatin. Neuron nucleus progressively shrinks but apoptotic nucleus fragmentation is not occurred. This neuron death type is delayed necrosis. Nuclei of the satellite glial cells also shrink. In 8 h after PDT treatment some of them become fragmented that is characteristic for apoptosis, whereas others lose the plasma membrane integrity and die through necrosis. However, glial cells not only die but also proliferate under PDT treatment and their number is increased. This gliosis is probably aimed to neuron saving.