[Effect on expression of vascular smooth muscle cell calcium channel in rats exposed in low temperature].

OBJECTIVE: To observe the expression of vascular smooth muscle cells calcium channel α1C subunit (LTCCα1C) in rats exposed in low temperature. METHODS: Cold-induced hypertension was established and blood pressure was measured every two weeks. The mRNA expression of L type calcium channel α1C was determined by RT-PCR. RESULTS: The blood pressure of the rats exposed to cold environment increased. The blood pressure of experimental groups [(102.8 ± 2.25) mm Hg] began to increase from the first two weeks, compared with the control group [(89.2 ± 3.73) mm Hg], there were significant difference (P < 0.05). The blood pressure of experimental groups were (114.5 ± 4.21), (121.9 ± 3.03) mm Hg respectively at 4, 6 weeks. Compared with the control group, the expression of LTCCα1C mRNA of the cold exposure group increased significantly (P < 0.01). There was a significant correlation between the expression of LTCCα1C mRNA and the blood pressure of the rats (r = 0.86, P < 0.01). CONCLUSION: Repeated cold exposure can establish cold-induced hypertension, and the level of vascular smooth muscle cells LTCCα1C expression increase.

[Cardiovascular circulation feedback control treatment instrument].

The cardiovascular circulation feedback control treatment instrument (CFCTI) is an automatic feedback control treatment system, which has the function of monitoring, alarming, trouble self-diagnosis and testing on the line in the closed loop. The instrument is designed based on the successful clinical experiences and the data are inputted into the computer in real-time through a pressure sensor and A/D card. User interface window is set up for the doctor's choosing different medicine. The orders are outputted to control the dose of medicine through the transfusion system. The response to medicine is updated continually. CFCTI can avoid the man-made errors and the long interval of sampling. Its reliability and accuracy in rescuing the critical patients are much higher than the traditional methods.

Relationship between hOGG1 Ser326Cys gene polymorphism and coronary artery lesions in patients with diabetes mellitus.

To study the relationship between human 8-oxoguanine glycosylase (hOGG1) Ser326Cys gene polymorphism and coronary artery lesions in patients with diabetes mellitus, we analyzed 323 patients with diabetic mellitus, who underwent coronary angiography. Using PCR-RFLP, these patients were grouped into three genotypes: Cys/Cys (n=85), Ser/Ser (n=121), and Ser/Cys (n=117). Several clinical data, including history of diseases and biochemical indices were recorded. hOGG1 mRNA expression and 8-hydroxy deoxyguanosine (8-OHdG) were measured by RT-PCR and ELISA, respectively. The quantities and severity of coronary artery with lesions were analyzed from coronary angiography. The Gensini and SYNTAX scores were detected by the unitary criteria. The 8-OHdG levels showed statistical difference among the three genotypes (F=21.56, P<0.05). Also, 8-OHdG in Cys/Cys genotype was higher than Ser/Ser and Ser/Cys genotype (q=2.32, q=3.12, P<0.05). In terms of the expression of hOGGl mRNA, the measure of hOGGl/ß-actin showed significant difference among the three groups (F=12.56, P<0.05). On comparing two groups, hOGGl/ß-actin in Cys/Cys genotype was higher thanSer/Ser and Ser/Cys genotypes (q=2.32, q=3.12, P<0.05). Percentage of 3-vessel lesions was high in Cys/Cys genotype and percentage of 1-vessel lesions was low in Ser/Cys genotype. Gensini and SYNTAX scores and ratio of complex lesions were significantly higher in the Cys/Cys genotype than the other two genotypes (FGensini=47.16, FSYNTAX=55.12; P<0.05). hOGG1 Ser326Cys polymorphism showed correlation with coronary artery lesions in patients with diabetes mellitus, and Cys/Cys genotype may have more impact on the severity of lesions.

Exploring in vitro roles of siRNA in cardiovascular disease.

RNA interference (RNAi) is an adaptive defense mechanism through which double stranded RNAs silence cognate genes in a sequence-specific manner. It has been employed widely as a powerful tool in functional genomics studies, target validation and therapeutic product development. Similarly, the application of small interfering RNA (siRNA) to the silencing of the disease-causing genes involved in cardiovascular diseases has made great progress. In this overview, we attempt to provide a brief outline of the current understanding of the mechanism of RNAi and its potential application to the cardiovascular system, with particular emphasis on its ability to identify the pathophysiological function of genes related to several important cardiovascular disorders. The prospects of RNAi-based therapeutics, as well as the advantages and potential problems, are also discussed.