The Influence Of Propofol On The Functional Status Of Neurocytes By Regulating The THBS-1 Level Of Astrocytes

Objective:①To observe the effects of propofol anesthesia on the functional protein of astrocytes and neurons in rat cortex.②To detect the THBS-1 mRNA and protein level of the cultured rat cortical astrocytes in different propofol treat groups.③To compare the influence of propofol on synapses and neurite outgrowth between the stand-alone cultured neuron and co-cultured neuron with astrocytes.Methods:①The general anesthesia model of rat using propofol was established firstly. The rat brain tissue slices were used to detect the functional proteins of astrocytes and neurons by immunohistochemisty.②Astrocytes were isolated from pooled rat cortex and grown in culture, then exposed to propofol with different concentrations or different time. The mRNA level of thrombospondin 1 (THBS-1) was detected by RT-PCR, and the protein level of THBS-1 by immunofluorescence cytochemistry and Western blotting.③The rat cortical neurons were cultured in two different ways, co-coltured with astrocytes or stand-alone cultured. Then the cells were treated with different concentrations of propofol. Immunofluorescence cytochemistry was applied to display the state of neuron synapses and neurites.Results:①The THBS-1 level was increased in rat cortex after intraperitoneal administration of propofol.②The mRNA and protein level of THBS-1 in cultured rat cortical astrocytes was upregulated by propofol in a time and concentration dependent way. Exposure to 30μM propofol for 12 h may lead to the extreme changes in THBS-1 level.③The synapse density and neurite net intensity of the neurons that were co-cultured with astrocytes surpassed those of the stand-alone cultured ones. The shape change of the neurite was observed in the 300μM propofol exposed group. Even higher synapse density was detected in the co-cultured neurons treated with 30μM propofol.Conclusions:The level of THBS-1 secreted by asrtocytes in the rat cortex could be upregulated in a time and dose dependent way when exposed to propofol. The growth state of cultured neuron can be improved by co-culturing with astrocytes. Propofol can influence the synapse density of the co-cultured neurons.