Horizontal cells (HCs) mediate negative feedback to photoreceptors. In the mammalian retina, there are two types of HCs, which are extensively coupled to neighboring cells through homologous gap junctions. The permeab...Horizontal cells (HCs) mediate negative feedback to photoreceptors. In the mammalian retina, there are two types of HCs, which are extensively coupled to neighboring cells through homologous gap junctions. The permeability and therefore the strength of feedback can be regulated by light intensity, dopamine and many other factors. However, the component(s) of the most prominent gap junctions, those between A-type HCs in the rabbit retina, is still unknown. In this study, we compared the sequences of many types of mammalian connexins, obtained partial sequences of rabbit connexin 50 and 57. Using specific primers designed against the rabbit sequences, we identified mRNAs of connexin 50 and/or 57 in visually selected single A-type HC using multiplex RT-PCR.展开更多
Endostatin is a natural occurred angiogenesis inhibitor derived from collagenXVIII. So far its function during the angiogenesis process of bone formation and arthropathy has not been well studied yet. The present stud...Endostatin is a natural occurred angiogenesis inhibitor derived from collagenXVIII. So far its function during the angiogenesis process of bone formation and arthropathy has not been well studied yet. The present study addresses the function of endostatin in rabbit articular chondrocytes (RAC). We found that endostatin can promote RAC adhesion and spreading as well as its proliferation. In monolayer cultured RAC, CollagenII, TIMP1 and collagenXVIII transcription were up regulated by endostatin while collagenI and MMP9 were down regulated. Moreover collagenXVIII and endostatin antigens are present at synovial fluid. These findings indicate new function of endostatin as a homeostatic factor in cartilage metabolism.展开更多
基金supported by a MOST Major State Basic Research Program Grant to the Institute of Neuroscience(G2000077800)NSFC project grants(30170305,30270460)to SH
文摘Horizontal cells (HCs) mediate negative feedback to photoreceptors. In the mammalian retina, there are two types of HCs, which are extensively coupled to neighboring cells through homologous gap junctions. The permeability and therefore the strength of feedback can be regulated by light intensity, dopamine and many other factors. However, the component(s) of the most prominent gap junctions, those between A-type HCs in the rabbit retina, is still unknown. In this study, we compared the sequences of many types of mammalian connexins, obtained partial sequences of rabbit connexin 50 and 57. Using specific primers designed against the rabbit sequences, we identified mRNAs of connexin 50 and/or 57 in visually selected single A-type HC using multiplex RT-PCR.
文摘Endostatin is a natural occurred angiogenesis inhibitor derived from collagenXVIII. So far its function during the angiogenesis process of bone formation and arthropathy has not been well studied yet. The present study addresses the function of endostatin in rabbit articular chondrocytes (RAC). We found that endostatin can promote RAC adhesion and spreading as well as its proliferation. In monolayer cultured RAC, CollagenII, TIMP1 and collagenXVIII transcription were up regulated by endostatin while collagenI and MMP9 were down regulated. Moreover collagenXVIII and endostatin antigens are present at synovial fluid. These findings indicate new function of endostatin as a homeostatic factor in cartilage metabolism.