| Postgraduate For Ph. D: Yuan Zhiguo Tutor Wang JunkeBone morphogenetic proteins ( BMPs) , also known as osteogenic proeins, ( OPs) ; cartilage - derived morphogenetic proteins, ( CDMPs) ; growth and differentiation factors, ( GDFs) , which are members of transforming growth factor - (TGF - ) superfamily.BMPs are synthesized as large precursor proteins. The core of the monomer is a cysteine knot involving six cysteine residues that are invariable spaced in the C - terminal region of all family members. Upon dimerization, they are proteo-lytically cleaved at a consensus Arg - X - X - Arg site to yield carboxy - terminal mature dimmers. Almost 30 members of BMPs have been isolated and classified according to structural similarities and differences.BMPs are distributed widely, including bone, heart, brain , kidneys and so on. Once secreted, the BMPs combined to receptors with serine - threonine ki-nase activity on cellular membrane. Once ligand binding, the typell receptor transphosphorylates the typel receptor at the juxtaposition region activating the typel kinase. The latter then transphosphorylates members of the Smad family of transcription factors that are subsequently translocated to the nucleus, where they activate the expression of target genes.BMP7 is an important member of the family of BMPs. It starts to be expressed during early gastrulation, localizing in the ectoderm of the periphery of the embryo, including the surface of ectoderm and the notochord, in the neuro-epithelium extending toward the prospective forebrain, and in the developing gutand optic vesicle, also expressed in the arial and ventricular chambers. This heart expression will continue throughout development.Recent researches have shown that many repair mechanisms are involved in post - ischemia injuries of organs. BMPs might reduce the renal injuries caused by ischemia. Other researches implied that BMP is closely related to the protection and treatment of brain and other important organs during ischemia/reperfusion with complex mechanism. People are gradually interested in the corresponding researches. Our study successfully set up animal model of acute cerebral and cardiac ischemia/reperfusion, to measure the expression changes of BMP7 gene during ischemia/reperfusion by RT - PCR, Western blot. At the same time, we apply intravenous anesthetics: propofol, which is routinely used in clinical anesthesia , to observe the effect of propofol on BMP7 gene expression during cardiac ischemia/reperfusion, and to observe and illustrate the anti - ischemia effect of porpofol in the view of molecular biology, and to provide the experimental foundation for clinical practice.Our study includes: Part one, the research of the changes of BMP7 gene expression during cerebral ischemia/reperfusion in rats. Part two, the influence of propofol on the BMP7 gene expression during cardiac ischemia/reperfusion.Materials1. Animals: Fifty-four wistar rats (body weight;200 -300g) were provided by the Experimental Animal Center, China Medical University.2. Main reagents and apparatus; RT -PCR kit, Wertern blot kit, multi-clonal antibody and other chemical agents. PCR machine, stable temperature water bath, electrophoretic machine, electrobalance, liquid nitrogen tank, section machine, multifunction blood analyse machine, Chemilmager5500, etc.Methods1. Expression of BMP7 gene during cerebral ischemia/reperfusion: 24wistar rats were randomly divided into 2 groups, control group (CC group) and ischemia group(CI group). In CI group, common carotid artery and external carotid artery were ligated after the exposure under local anesthesia with 1% lido-caine, then 4 - 0, nylon thread was inserted into the internal carotid artery at the bifucation and fixed at the end distal to the insertion. Thus the thread reached the proximal portion of the anterior cerebral artery. The origin of the right MCA and posterior communication artery were occluded. The thread was drawn back after two hou...
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