ABSTRACT
AIM: To study the effects of propofol on plasma membrane fluidity in PC12 cells and liposome,and its relevant mechanism. METHODS: Fluorescence depolarization method was used to measure values of fluorescence anisotropy, fluorescence polarization as well as microviscosity in PC12 cells and microviscosity in liposome continuously for 30 min. RESULTS: Propofol induced a significant decrease of fluorescence anisotropy, fluorescence polarization as well as microviscosity in PC12 cells, particularly in the first 5 min. After 5 min, the values of anisotropy were remained lower levels. Although propofol at concentration of 1 mg?L -1 had no effects on microviscosity in liposome, porpofol at concentration of 10 mg?L -1 and 100 mg?L -1 significantly decreased microviscosity in liposome. CONCLUTION: Propofol can significantly increase membrane fluidity in PC12 cells and liposome in a concertration dependent manner, and the anesthetic effect of propofol may be resulted from changes of membrane fluidity and structure of neurocyte.
ABSTRACT
AIM To study the effects of propofol on membrane fluidity and intracellular free Ca 2+ concentration ([Ca 2+ ] i ) in PC12 cells and discuss its relevant mechanism. METHODS PC12 cell lines were divided into seven groups: control, solvent and propofols(1,3,10,30,100 mg?L -1 ). Fluorescence depolarization method was used to measure dynamically microviscosity in PC12 cells and [Ca 2+ ] i was detected using calcium fluorescentprobe Fluo 3/AM and a laser scanning confocal microscope. RESULTS ①Acute administration of various doses of propofol induced a significant decrease of microviscosity in PC12 cells dose dependenty. ② Solvent, propofol at dose of 10 mg?L -1 had no effect on [Ca 2+ ] i in PC12 cells, however, after 30 and 100 mg?L -1 administration, [Ca 2+ ] i increased markedly at 20～30 seconds (increase percentage were 119% and 140% respectively) and then recovered to their pre administration levels within 50 seconds. CONCLUSION The propofol can significantly increase membrane fluidity in PC12 cells in a dose dependent manner and elevate [Ca 2+ ] i in PC12 cells at doses of 30 and 100 mg?L -1 . These changes are consistent with each other and related closely with anesthetic effect of propofol.
ABSTRACT
To elucidate the latest progress of proteomics research of central nervous system diseases and drugs. Proteomics , an important discipline in postgenomic era, is the integrated study of protein properties on a large scale. Currently, the best established application of proteomics are in the clinical and biomedical fields. Proteomics will facilitate the elucidation of network mechanism of the development, progress and prognosis of central nervous system diseases. Proteomics offer a unique opportunity to identify disease specific proteins, accelerate the development of target driven drugs, build up molecular pharmacological models, screen and analysis of the efficacy, toxicity and side effects of potential drugs on a large scale. It is predictable that proteomics will play a tremendous role for the diagnosis, detection and pharmaceutical development of central nervous system diseases.