Effects Of Formaldehyde On NO/cGMP Passway In Rat Vessel And Heart

With the improvement of living standards,people have more attention to the various environmental pollutants on their health.Formaldehyde as a typical representative of indoor pollutants,is subject to wide attention.Related reports have clearly indicated that formaldehyde is one of the harmful substances that cause abnormal tone of artery and hearts' injury.Formaldehyde also has a certain role to induce the occurrence of atherosclerosis,myocardial infarction and other cardiovascular diseases.Our previous study on the effects of formaldehyde on vascular tone found that formaldehyde causes vascular ring tension mechanism,and that may be related to NO/cGMP signal path,BKca channel,and L-Ca²⁺ channel.In this study,we based on previous studies did further study.We tested the enzyme activity,gene expression and protein of NO/cGMP signal path and two kinds of ion channels(L-Ca²⁺ channels and BKca channel).In the study,we chose 72 male SD rats about 200 g,and randomly divided into four groups,namely control group,low concentration group?0.5 mg/m3?,the concentration of group?3 mg/m3?and high concentration group?18 mg/m3?.These rats would accept static formaldehyde inhalation experiments.Fumigation period is of 4 h/d,for one week?7 d?.After the last fumigation completed,these rats were killed in 24 h.The arteries and hearts of rats were took out and quickly frozen in liquid nitrogen.Then,we using the Western Blot,real-time quantitative RT-PCR,enzyme activity assays and other biochemical and molecular biological techniques and methods associated mRNA,protein,enzyme activity and so do related testing experiments.The results showed that formaldehyde effects on the heart and blood vessels is similar:?1?The mRNA,protein and enzyme activity of eNOS were inhibited by formaldehyde,and there is a dose-response relationship;?2?Formaldehyde promote iNOS expression in a large number,and have a dose-response relationship;?3?Formaldehyde can increase the content of NO and cGMP significantly;?4?The mRNA and protein expression of Cav1.2 and Cav1.3 subject to formaldehyde inhibition;?5?The mRNA expression levels of BKca?and BKca?1 channels subject to formaldehyde enhancement.These results showed that different concentrations of formaldehyde can elevate content of NO and cGMP in arteries and hearts;can reduce gene and protein expression of Cav1.2 and Cav1.3;and can increase gene expression of BKCa?and BKCa?1 channel.Thus,formaldehyde induced cardiovascular disease may be by regulating the NO/cGMP signaling pathway,the L-Ca²⁺ channels and BKca channel in the heart and blood vessels.