Comparison of arylalkylamine N-acetyltransferase and melatonin receptor type 1B immunoreactivity between young adult and aged canine spinal cord

Melatonin affects diverse physiological functions through its receptor and plays an important role in the central nervous system. In the present study, we compared immunoreactivity patterns of arylalkylamine N-acetyltransferase (AANAT), an enzyme essential for melatonin synthesis, and melatonin receptor type 1B (MT2) in the spinal cord of young adult (2~3 years) and aged (10~12 years) beagle dogs using immunohistochemistry and Western blotting. AANAT-specific immunoreactivity was observed in the nuclei of spinal neurons, and was significantly increased in aged dog spinal neurons compared to young adult spinal neurons. MT2-specific immunoreactivity was found in the cytoplasm of spinal neurons, and was predominantly increased in the margin of the neuron cytoplasm in aged spinal cord compared to that in the young adult dogs. These increased levels of AANAT and MT2 immunoreactivity in aged spinal cord might be a feature of normal aging and associated with a feedback mechanism that compensates for decreased production of melatonin during aging.

HGF prolongs the survival period of primary cultured rat spinal neurons / 基础医学与临床

Objective To explore the protective effect of HGF on primary cultured spinal neurons in vitro.Methods Cultured neurons were transfected with Ad-GFP or Ad-HGF in different multiplicity of infection(MOI),then flow cytometer and PI-Hoechst double stains were used to assay transfer rate or to determine the status of cells respectively.ELISA was used to detect the expression of HGF in Ad-HGF transfected neurons,and the activity of neurons was judged by neutral red stain,MTT and NSE-ELISA methods.Results After transfection with Ad-GFP in MOI of 50,the transfer rate was high as detected by flow cytometer,and the status of cells was well as judged by PI-Hoechst double stain.The results of ELISA showed that HGF was expressed in medium.After transfection with Ad-HGF,the activity of neurons was better than neurons without treatment(P

INTERRELATION BETWEEN MICROTUBULE-ASSOCIATED PROTEIN 5 AND LYSOSOME IN CULTURED SPINAL NEURONS FROM THE RAT / 解剖学报

Objective To investigate the interrelation between microtubule associated protein 5 and lysosome in cultured spinal neurons. Methods Neuron culture, immunofluorescence cytochemistry, laser confocal scanning microscope were used. Results In cultured spinal neurons, both of MAP5 and calthepsin D were distributed in cytoplasm and processes. In merged pictures, the distribution of MAP5 and calthepsin D was almost similar. When nocodazole was employed, the distribution of MAP5 and calthepsin D changed simultaneously. Both fluorescence distributed in cytoplasm was uneven and the process was shorter. When PMA was employed, the distribution of red and green fluorescence became reticulum and spread toward membrane. The soma enlarged and the process displayed certain direction accompanying adjacent processes interlinked.Conclusion In cultured spinal neurons, the distributions of MAP5 and lysosomes were almost similar. Both were in cytoplasm and process. Nocodazole and PMA caused reverse change for the distribution of MAP5 and lysosomes. The distribution of MAP5 and calthepsin D treatel with Nocodazole was unregulated, while PMA was regulated and loose. These results suggested that MAP5 and lysosomes were interrelated between structure and function. Both of them were depended on the integrity of microtubule.