Aim To research the effects of total flavones of rhododendra(TFR)on transient receptor potential vanilloid receptor 4(TRPV4)in cerebral basilar arteries(CBA)of rats subjected to ischemia/reperfusion(IR)injury.Methods The model of total brain IR was established by four-artery occlusion(4-VO)method in rats.Arterial pressure perfusion and cell membrane potential recording methods were used for surveying the dilatation and hyperpolarization of TFR and ruthenium red(RR,an inhibitor of TRPV4)in the KCl-preconstricted CBA ex vivo in rats subjected to IR.Quantitative real-time polymerase chain reaction(qRT-PCR)and Western blot were utilized to investigate the TRPV4 mRNA and protein expressions of TFR and RR in cerebrovascular endothelial cells of CBA in vivo in rats subjected to IR.Results 11～2 700 mg·L-1 TFR significantly induced concentration-dependent hyperpolarization and dilatation in the KCl-preconstricted CBA in rats subjected to IR.TFR still produced degenerative hyperpolarization and dilatation by removal of endothelium in CBA,which was remarkably attenuated as compared with endothelium-intact group(P<0.01).After removal of NO and PGI2 vasodilatation,TFR obviously elicited the hyperpolarization and dilatation that were further decreased by RR(an inhibitor of TRPV4)in IR CBAs.TFR pretreatment apparently increased the level of TRPV4 mRNA and protein expressions in IR CBAs.These effects were restrained by RR,an inhibitor of TRPV4.Conclusions TFR could mediate endothelium-dependent and endothelium-independent effects.The endothelium-derived dilatation may be related to the increase of endothelium activity and endothelium-derived hyperpolarizing factor(EDHF)generation and release that have been promoted by TFR,and secondarily activating TRPV4,which results in Ca2+ inflow and subsequent hyperpolarization of vascular smooth muscle cell membrane and vasorelaxation.

Objective:This study aimed to explore the feasibility and clinical value of monitoring the progression of early kidney injury in type 2 diabetic patients by assessment of the urinary C-terminal agrin fragment (uCAF) with enzymatic chemiluminescence immunoassay.Methods:A total of 251 patients with type 2 diabetes, who attended the Second Affiliated Hospital of Wenzhou Medical University from October 2018 to March 2020, were included in this retrospective analysis. One hundred and fifty-six participants undergoing health check-up at the Second Affiliated Hospital of Zhejiang University School of Medicine in February 2021 served as controls. Basic clinical information, glycosylated hemoglobin type A 1c and serum creatinine values were recorded, and urine specimens were collected for urinary creatinine, urinary α 1 microglobulin(uα 1M), urinary immunoglobulin G (uIgG), urinary albumin, urinary N-Acetyl-B-D-glycosaminidase (uNAG) and uCAF measurements. Based on the estimated glomerular filtration rate (eGFR), 251 patients were classified into G1~G5 stage groups with 116, 22, 28, 55 and 30 patients in each group. One hundred and sixty-six patients with early diabetic kidney disease (stage G1-G3) were divided into subgroups A1 (79), A2 (48) and A3 (39) according to the urinary albumin/creatinine ratio (UACR), the uα1M levels were divided into uα1M subgroup 1 (83 cases), uα1M subgroup 2 (42 cases), and uα1M subgroup 3 (41 cases), and uIgG subgroup 1 (83 cases), uIgG subgroup 2 (42 cases), and uIgG subgroup 3 (41 cases) according to uIgG levels. The Spearman method was used to analyze the correlation between uCAF levels and eGFR, UACR, uα1M and uIgG levels. Results:(1) The linear range of the uCAF detected by enzymatic chemiluminescence immunoassay was 3.97-2 000.00 ng/ml, with a detection limit of 2.28 ng/ml, intra-batch coefficients of variation of 1.15% and 1.57%, inter-batch coefficients of variation of 1.63% and 5.78%, and a biological reference interval of <95.35 μg/g Cr. (2) The uCAF level and positive rate (UACR≥30 mg/g) increased with the decrease of eGFR from G1-G3, uCAF level was negatively correlated with eGFR value ( r=-0.543, P<0.000 1), and the positive rate increased from 24.14% (28/116) to 85.71% (24/28) from G1-G3. The uCAF level and positivity rate decreased with the decrease of eGFR from G4 to G5. uCAF level was positively correlated with eGFR value ( r=0.495, P<0.001), and the positivity rate decreased from 30.91% (17/55) to 23.33% (7/30) from G4 to G5. (3) In patients with early diabetic kidney disease, uCAF levels and positivity rates increased gradually with the increase of UACR. uCAF levels were positively correlated with UACR values ( r=0.602, P<0.001), and the uCAF positivity rate reached 21.52% (17/79) in the A1 subgroup. (4) uCAF level was positively correlated with uα1M and uIgG levels in patients with early diabetic kidney disease ( r=0.757, 0.596, both P<0.001). Conclusion:Analytical performance of enzyme chemiluminescence immunoassay for the detection of CAF is satisfactory and could be used a biomarker for monitoring damage and progression of early diabetic kidney disease in patients with type 2 diabetes.