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Objective To investigate whether hepatocyte growth factor ( HGF ) and insulin-like growth factor (IGF1) induce cardiac stem cells (CSCs) to proliferate and directly differentiate into cardiomyocytes in vitro.Methods The myocardial tissues were dissected for primary culture of CSCs with the method of explants .The expressions of c-kit and CD34 were examined with immunofluorescence .Primary cells were purified with c-kit by flow cytometry.CFDA SE fluorescent probe was used to detect the proliferation of c-kit+CSCs.C-kit +CSCs were divided into two groups , and cardiac stem cells group and co-cultured with cardiomyocytes group , both group were cultured with HGF and IGF 1.An inverted microscope was used to observe changes in cell number and morphology in different periods .Living cells workstation was used to observe CFDA SE fluorescence intensity , to acquire images and do statistical analysis .Immunofluorescence technique was used to detect the expression of Nkx 2.5 and cardiac troponin T .Results In cardiac stem cells group ,CSCs had no obvious changes in cell number .In co-cultured with cardiomyocytes group , CSCs proliferated and had changes in morphology .Nkx2.5 and cTnT were positively expressed . Several CSCs differentiated into beating cardiomyocytes . Conclusion In co-cultured with cardiomyocytes condition , HGF and IGF1 may promote CSCs to proliferate and differentiate into beating cardiomyocytes .
ABSTRACT
BACKGROUND: Neuropeptide Y (NPY) neurons are extensively located in various brain regions such as cerebral cortex, caudate-putamen nucleus, syslimbic system, thalamus and brain stem. They are also involved in various brain activities such as motor learning, motor memory and motor integration. Considering the fact that cerebellum can reorganize through motor learning, we tried to identify the morphology and distribution of NPY neurons in rat's cerebellar cortex to obtain the morphologic knowledge that is related to its cerebellar-cortex-based motor learning.OBJECTIVE: To investigate the morphology and distribution of NPY -immunoreactive neurons in rat's cerebellar cortex, and discuss the relationship between NPY neurons and cerebellum motor learning and motor memory.DESIGN: A single-sample-study based on animal samples.SETTING: Anatomy Department, Pathophysiology Department and Morphology Center in Xinxiang Medical College.MATERIALS: From July to December 2001, the experiment was performed at the Morphology Center in Xinxiang Medical College. Ten Sprague-Dawley (SD) rats, clean grade, regardless of their gender and weighing 100-200 g,were selected.METHODS: After intraperitoneal injection anesthesia and ascending aorta infusion fixation, the cerebellum was taken out by craniosurgery. The cerebellum was immersed in the same fixative fluid for duration of 48 hours, and then was embedded in paraffin. The next step was to make continuous sagittal sections. NPY neurons were identified by SP immunohistochemical staining, using rats cerebral section as the positive control. In the negative control, the first antibody replaced by Bovine Calf Serum(BCS), and the second antibody replaced by 0.01 mol/L PBS. Sequentially the light-microscopic observation and micrography were recorded.MAIN OUTCOME MEASUREMENTS: The Morphology and distribution of NPY neurons in rat's cerebellar cortex were taken as main outcome measurements.RESULTS: NPY-immunoreactive neurons were distributed in the Purkinje layer of the cerebellum. They had pear-like or spherical shapes, clear and unstained nucleus, unstained axons and dendrites, and their axons stretching out into the granular layer while the reticular dendrites elongated into the molecular layer. NPY-immunoreactive fibers, instead of neurons, were found in the molecular layer and granular layer.CONCLUSION: NPY-immunoreactive neurons in the Purkinje layer of the cerebellum may be involved in motor learning, motor memory, visceral activity and higher motor integration.
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Objective To investigate cell type and size of fetus atrioventricular node. Methods Using the technique of paraffin section, H-E staining, the cellular morphology and size of atrioventricular node in fetus hearts were observed under microscope, and quantitied by HIPAS-1000 computerized image analytical instrument. Results The cell types of atrioventricular node in fetue hearts were composed of light, dark and transitional cells. The morphology of light and dark cells were spindle-shaped or ellipsoid, but a few cells were polygonal. The shape of transitional cells was short column. The nuclei of light cells and transitional cell were larger than that of dark cells.Conclusion Pacemaker cell of atrioventricular node in fetus heart includes light and dark cells which could present different function types of pacemaker cell. [