The Effect Of Lead On Vascular Smooth Muscle Cell Apptosis And Proliferation

Lead (Pb) exists widely in nature. Lead and its most compounds’ are notdegradation of the environment pollution. Lead has many aspects of toxicity.Its can damage to human body organs and systems. Cardiovascular disease isthe serious harm our country people’s health and life. Numerous studies havedemonstrated. High blood pressure is the disease of the most important riskfactors. In recent years, many people found lead can raise blood pressure ofanimals. Epidemiological studies indicated that lead has significant correlationwith high blood pressure and atherosclerosis. Lead has been identified as ahazard and a risk factor for hypertension development and othercardiovascular diseases. The impact of Pb on development of hypertensionand cardiovascular diseases is still not clear.Proliferating Cell Nuclear Antigen (PCNA) is a kind of DNA synthesis incells closely protein. It can be used as a biomarker to assess cell proliferation.B cell lymphoma/lewkmia-2(Bcl-2) is a kind of the original cancer gene. It hasthe function of inhibiting cell apoptosis. Bax is important different dimers withmolecules. Bax promote cell apoptosis. Bax were identified. Because bax withbcl-2protein is the common immune deposits. Bcl-2/Bax ratio is the lower,cell apoptosis is the easier.Objective: This experiment with SD rats’ low levels of lead exposure is amodel. Observation lead exposure of40days， SD rats blood vesselsvalue-added, apoptosis. We will observe lead exposure to harm the bloodvessels and explore lead to the blood vessel damaging mechanism ofmolecular biology.Methods:1Experimental animalSelect health,3-4Zhou Ling, weight is in99-114g SD rats only24. Experimental animals by he bei medical university center for animalexperiments.2The experiment reagentLead acid end density is1%.3The experiment groupWe will divide SD rats into two groups by random number table method.The one group is the control group which group has12SD rats. The othergroup is the experimental group which group has12SD rats, too. Theexperimental group drinks1%lead acid water. The control group drinks water.After40days, SD rats would be put to death.4Observation of structure changes in blood vessels of SD rats by H.E.staining method.5With Western blot mark method to detect SD rats’ blood vessels invalue-added protein PCNA, apoptosis proteins Bcl-2and Bax. The resultsusing the computer semi-quantitative analysis technology.6Localization and semi-quantitative analysis of PCNA, Bcl-2and Bax proteinexpression in blood vessels by immunohistochemistry. The results usingcomputer immunohistochemical image analysis technique for analysis.Results:1Observation of structure changes in blood vessels of SD rats by H.E.staining method.The experiment group is the vascular cavity of rat expansion pipe, tubewall ruffle reduce, the nucleus shrinks and elastic membrane ruffle.2Lead to SD rats’ blood vessels in the influence of PCNA protein expressionWestern blot results showed that the lead group with the quantity ofPCNA protein expression is significant difference from the control group. Thelead group expression is significantly less(P＜0.05).Computer Western blot image half quantitative analysis, the result shows:the lead group of PCNA protein mean grey value significantly lower thannormal control group (P <0.05). Lead can reduce in the blood essels of PCNAprotein expression. Immunohistochemical results showed that immunohistochemicalreactants of PCNA protein are tan-yellow color. It mainly expresses in SD ratsvascular smooth muscle cell nuclei. The experiment group of tan particles aresignificantly more than the control group(P＜0.05).Computer immunohistochemical image analysis shows that in thecomparison of the mean density, mean density of the lead group are lower thanthose of the control group, the difference between a significant difference (P <0.05). Lead can reduce PCNA that lead in rat blood essels expression instrength.3Lead to SD rats blood vessels in apoptosis protein Bcl-2the influence ofexpressionWestern blot results showed that the lead group with the quantity of Bcl-2protein expression is significant difference from the control group. The leadgroup expression is significantly less(P＜0.05).Computer Western blot image half quantitative analysis, the result shows:the lead group of Bcl-2protein mean grey value significantly lower thannormal control group (P <0.05). Lead can reduce in the blood essels of Bcl-2protein expression.Immunohistochemical results showed that immunohistochemicalreactants of Bcl-2protein is tan-yellow color. Bcl-2protein mainly expressesin SD rats vascular smooth muscle cytoplasm. The experiment group of tanparticles are significantly more than the control group(P＜0.05).Computer immunohistochemical image analysis shows that in thecomparison of the mean density, mean density of the lead group are lower thanthose of the control group, the difference between a significant difference(P <0.05). Lead can reduce Bcl-2that lead in rat blood essels expression instrength.4Lead to SD rats’ blood vessels in apoptosis protein Bax the influence ofexpressionWestern blot results showed that the lead group with the quantity of Baxprotein expression is significant difference from the control group. The lead group expression is significantly less(P＜0.05).Computer Western blot image half quantitative analysis, the result shows:the rat Bax protein is significantly higher than the average gray value of thecontrol group (P <0.05). Lead can promote in the blood essels Bax proteinexpression.Immunohistochemical results showed that immunohistochemicalreactants of Bax protein is tan-yellow color. Bax protein mainly expresses inSD rats vascular smooth muscle cytoplasm. The experiment group of tanparticles are significantly more than the control group(P＜0.05).Computer immunohistochemical image analysis shows that Mean densityof the comparison, the average light density values of the samples were higherthan those in the control group, the difference between a significant difference(P <0.05). That can lead to promote Bax in rat blood essels expression instrength.Conclusions:1Short-term exposed to lead, the experiment group is the rats vascular cavityexpansion pipe, tube wall ruffle reduce, the nucleus shrinks, and elasticmembrane ruffle.2Short-term exposed to lead, the lead group can be induced to blood vesselcells apoptosis. The lead group can make PCNA protein expression todecrease, Bcl-2protein expression to decrease and Bax protein expression toincrease.Bcl-2/Bax ratio reduced. It improves blood cell apoptosis.3The experiment group is the rats’ vascular cavity expansion pipe and elasticmembrane ruffle. Abnormal blood vessel cells may be one of the reasons whyapoptosis.