OBJECTIVE: To explore the effect of telmisartan on the expression of metadherin in the kidney of mice with unilateral ureter obstruction. METHODS: Eighteen male C57 mice were randomized into sham-operated group, model group and telmisartan treatment group. In the latter two groups, renal interstitial fibrosis as the result of unilateral ureter obstruction (UUO) was induced by unilateral ureteral ligation with or without telmisartan intervention. Renal pathological changes of the mice were assessed using Masson staining, and immunohistochemistry and Western blotting were used to detect the expression of extracellular matrix proteins and metadherin in the kidney of the mice. In the experiment, cultured mouse renal tubular epithelial cells (mTECs) were stimulated with transforming growth factor-β1 (TGF-β1) and transfected with a siRNA targeting metadherin, and the changes in the expressions of extracellular matrix proteins and metadherin were detected using Western blotting. RESULTS: The expressions of extracellular matrix proteins and metadherin increased significantly in the kidney of mice with UUO ( < 0.05). Intervention with telmisartan significantly lowered the expressions of extracellular matrix proteins and metadherin and alleviated the pathology of renal fibrosis in mice with UUO ( < 0.05). In cultured mTECs, siRNA-mediated knockdown of metadherin obviously reversed TGF-β1-induced increase in the expressions of extracellular matrix proteins and metadherin. CONCLUSIONS Telmisartan can suppress the production of extracellular matrix proteins and the expression of metadhein to attenuate UUO-induced renal fibrosis in mice.
Angiotensin II Type 1 Receptor Blockers ; Animals ; Antihypertensive Agents ; Extracellular Matrix Proteins ; metabolism ; Fibrosis ; Kidney ; drug effects ; metabolism ; pathology ; Male ; Membrane Proteins ; genetics ; metabolism ; Mice ; Mice, Inbred C57BL ; RNA, Small Interfering ; Random Allocation ; Telmisartan ; pharmacology ; Transforming Growth Factor beta1 ; pharmacology ; Ureteral Obstruction ; complications ; metabolism

Fenofibrate, an agonist for peroxisome proliferator-activated receptor alpha (PPAR-α), lowers blood pressure, but whether this action is mediated via baroreflex afferents has not been elucidated. In this study, the distribution of PPAR-α and PPAR-γ was assessed in the nodose ganglion (NG) and the nucleus of the solitary tract (NTS). Hypertension induced by drinking high fructose (HFD) was reduced, along with complete restoration of impaired baroreceptor sensitivity, by chronic treatment with fenofibrate. The molecular data also showed that both PPAR-α and PPAR-γ were dramatically up-regulated in the NG and NTS of the HFD group. Expression of the downstream signaling molecule of PPAR-α, the mitochondrial uncoupling protein 2 (UCP2), was up-regulated in the baroreflex afferent pathway under similar experimental conditions, along with amelioration of reduced superoxide dismutase activity and increased superoxide in HFD rats. These results suggest that chronic treatment with fenofibrate plays a crucial role in the neural control of blood pressure by improving baroreflex afferent function due at least partially to PPAR-mediated up-regulation of UCP2 expression and reduction of oxidative stress.
Afferent Pathways ; drug effects ; Animals ; Antihypertensive Agents ; pharmacology ; Baroreflex ; drug effects ; Blood Pressure ; drug effects ; Fenofibrate ; pharmacology ; Male ; Oxidative Stress ; drug effects ; PPAR gamma ; drug effects ; metabolism ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects ; Transcriptional Activation ; drug effects ; Uncoupling Protein 2 ; drug effects ; metabolism ; Up-Regulation

OBJECTIVES: Investigate the influence of benazepril and amlodipine on the expression of secretin (PZ) and somatostatin (SS) in spontaneously hypertensive rats (SHR). METHODS: Forty-five SHRs (14 weeks old, male) were randomly assigned into 3 groups (=15):SHR group, Benazepril group (which was given benazepril 0.90 mg·kg·d) and Amlodipine group (SHRs were given amlodipine 0.45 mg· kg·d), taking WistarKyoto(WKY) as normal control (=15), meanwhile, rats in SHR group and WKY group were given the same volume of distilled water. After 8 weeks of intervention, the expression of protein and mRNA of PZ in duodenum and SS in sinuses ventriculi was detected by enzyme-linked immunoassay and RT-PCR. RESULTS: After 8 weeks of intervention, compared with the WKY group, the expression of protein and mRNA of PZ in duodenum and SS in sinuses ventriculi was increased significantly in SHR group (<0. 05). Compared with SHR group, the expression of PZ in duodenum and SS in sinuses ventriculi was decreased significantly in Benazepril group and Amlodipine group (<0.05). Compared with Benazepril group, in Amlodipine group the expression of PZ mRNA in duodenum and SS mRNA in sinuses ventriculi was decreased more significantly (<0.05). CONCLUSIONS The regulation disorder of PZ in duodenum and SS in sinuses ventriculi exists in SHR. The antihypertensive effect of benazepril and amlodipine may be realized by regulating the expression of PZ and SS, while the regulation of amlodipine is more obvious than benazepril.
Amlodipine ; pharmacology ; Animals ; Antihypertensive Agents ; pharmacology ; Benzazepines ; pharmacology ; Blood Pressure ; Hypertension ; drug therapy ; Male ; Random Allocation ; Rats ; Rats, Inbred SHR ; Rats, Inbred WKY ; Secretin ; metabolism ; Somatostatin ; metabolism

This study aimed to investigate the antihypertensive effect and possible mechanism of Dendrobium officinale flos on hypertensive rats induced by high glucose and high fat compound alcohol. The hypertensive models were successfully made by high-glucose and high-fat diet, with gradient drinking for 4 weeks, and then divided into model control group, valsartan (5.7 mg·kg⁻¹) positive control group and D. officinale flos groups (3，1 g·kg⁻¹). After 6 weeks of treatment, the blood pressure of rats was measured regularly. After the last administration, endothelin-1 (ET-1), thromboxane B₂ (TXB₂), prostacyclin (PGI₂) and nitric oxide (NO) were tested. Endothelial nitric oxide synthase (eNOS) expression and lesion status in thoracic aorta were detected. The vascular endothelium dependent dilation of the thoracic aorta was detected by the isolated vascular loop tension test. The results showed that D. officinale flos could significantly reduce systolic blood pressure and mean arterial pressure in hypertensive rats, inhibit the thickening of thoracic aorta and the loss of endothelial cells, reduce plasma content of ET-1 and TXB₂, and increase the content of PGI₂ and NO. After long-term administration, vascular endothelium dependent dilation of the thoracic aorta was significantly increased, and could be blocked by the eNOS inhibitor (L-NAME) and increase the expression of eNOS. Therefore, D. officinale flos has an obvious antihypertensive effect on high glucose and high fat compound alcohol-induced hypertensive rats. Its mechanism may be correlated with the improvement of vascular diastolic function by protecting vascular endothelial cells, and finally resist hypertension.
Animals ; Antihypertensive Agents ; pharmacology ; Blood Pressure ; Dendrobium ; chemistry ; Diet, High-Fat ; Drugs, Chinese Herbal ; pharmacology ; Endothelin-1 ; blood ; Endothelium, Vascular ; drug effects ; Epoprostenol ; blood ; Glucose ; Hypertension ; chemically induced ; drug therapy ; Nitric Oxide ; blood ; Nitric Oxide Synthase Type III ; metabolism ; Rats ; T-Box Domain Proteins ; blood ; Vasodilation

This study was amid to construct the pharmacophore model of L-type calcium channel antagonist in the application of screening Drugbank and TCMD. This paper repositions the approved drugs resulting from virtual screening and discusses the relocation-based drug discovery methods, screening antihypertensive drugs with L-type calcium channel function from TCMD. Qualitative hypotheses wre generated by HipHop separately on the basis of 12 compounds with antagonistic action on L-type calcium channel expressed in rabbit cardiac muscle. Datebase searching method was used to evaluate the generated hypotheses. The optimum hypothesis was used to search Drugbank and TCMD. This paper repositions the approved drugs and evaluates the antihypertensive effect of the chemical constituent of traditional Chinese medicine resulting from virtual screening by the matching score and literature. The results showed that optimum qualitative hypothesis is with six features, which were two hydrogen-bond acceptors, four hydrophobic groups, and the CAI value of 2.78. Screening Drugbank achieves 93 approved drugs. Screening TCMD achieves 285 chemical constituents of traditional Chinese medicine. It was concluded that the hypothesis is reliable and can be used to screen datebase. The approved drugs resulting from virtual screening, such as pravastatin, are potentially L-type calcium channels inhibitors. The chemical constituents of traditional Chinese medicine, such as Arctigenin III and Arctigenin are potentially antihypertensive drugs. It indicates that Drug Repositioning based on hypothesis is possible.
Animals ; Antihypertensive Agents ; chemistry ; pharmacology ; Calcium Channel Blockers ; chemistry ; pharmacology ; Calcium Channels, L-Type ; genetics ; metabolism ; Drug Repositioning ; methods ; Molecular Structure ; Myocardium ; metabolism ; Rabbits

OBJECTIVETo observe the vasodilating effect of adrenomedullin 2 (ADM2) by antagonizing angiotensin 1 (Ang II), and to explore its mechanism.

METHODSEighteen male, 180-200 g SD rats were randomly divided into 3 groups (n = 6): control group, Ang II (150 ng/(kg x min)) group and Ang II (150 ng/(kg x min)) + ADM2(500 ng/(kg x h)) group. Mini-osmotic pumps filled with peptide were implanted in the back of rats subcutaneously. After two weeks, the blood pressure was measured by the way of carotid intubation. The plasma was collected for the detection of nitric oxide (NO) content and the activity of endothelial nitric oxide synthase (eNOS). The in situ oxidation of fluorescent dye dihydroethidium (DHE) was used for detecting superoxide in rat arteries. The rat isolated arterial rings were made for studying the vasodilating effect of ADM2. Human umbilical vein endothelial cell line EA. hy 926 cells were cultured and their intracellular reactive oxygen species (ROS) were evaluated by probe DCFH-DA.

RESULTSADM2 dramatically decreased the blood pressure in angiotensin II-induced hypertension rat model, enhanced plasma NO content and the activity of eNOS and reduced superoxide formation in vessel walls. ADM2 also induced relaxation of the vascular rings preconstricted by Ang II in a concentration-dependent and endothelium-dependent manner. In cultured vascular endothelium, ADM2 ameliorated the ROS generation induced by Ang II.

CONCLUSIONAdrenomedullin 2 relaxed blood vessels by antagonizing angiotensin II-induced oxidative stress and improving the vascular endothelial function.

Adrenomedullin ; pharmacology ; Angiotensin II ; pharmacology ; Animals ; Antihypertensive Agents ; pharmacology ; Blood Pressure ; drug effects ; Drug Antagonism ; Endothelium, Vascular ; drug effects ; Human Umbilical Vein Endothelial Cells ; cytology ; Humans ; Male ; Nitric Oxide ; blood ; Nitric Oxide Synthase Type III ; blood ; Oxidative Stress ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species ; metabolism ; Vasodilation ; drug effects

OBJECTIVETo explore the effect of puerarin combined with felodipine on the mRNA and protein expression of apelin and APJ in renal tissue of renovascular hypertensive rat.

METHODSixty-two Sprague-Dawley rats were used, of which 8 rats were randomly chosen as sham-operation group. The remaining rats were made for the rat model with renovascular hypertension. The renovascular hypertensive rats were randomly divided into 5 groups as follows: 4 groups which were treated with felodipine (0.8 mg x kg(-1) x d(-1)), puerarin (50 mg x kg(-1) x d(-1)), puerarin combined with felodipine (puerarin 25 mg x kg(-1) x d(-1) + felodipine 0.4 mg x kg(-1) x d(-1)) or captopril combined with felodipine (captopril 15 mg x kg(-1) x d(-1) x felodipine 0.4 mg x kg(-1) x d(-1)), and 1 group which was treated with distilled water. Drugs or distilled water were administered for 8 weeks. The expression of apelin and APJ mRNA and protein in ischemic and non-ischemic kidneys was assessed by RT-PCR or Western blot.

RESULTCompared with sham-operation group, the expression of apelin mRNA and protein in ischemic and non-ischemic kidneys in model group was increased significantly (P < 0.01); the expression of APJ mRNA and protein in ischemic kidneys had no significance, while that in non-ischemic kidneys was decreased (P < 0. 01). Compared with model group, the expression of apelin mRNA and protein in ischemic and non-ischemic kidneys was decreased significantly in all drug-treated groups (P < 0.01); while that of APJ mRNA and protein in non-ischemic kidneys was upregulated (P < 0.01). Compared with felodipine group, the expression of apelin mRNA and protein in ischemic and non-ischemic kidneys was decreased (P < 0.01 or P < 0.05) in the group treated with both puerarin and felodipine; and the expression of APJ mRNA and protein in ischemic kidneys did not reach significant level, however, that was upregulated in non-ischemic kidneys (P < 0.01 or P < 0.05).

CONCLUSIONPuerarin downregulates the expression of apelin mRNA and protein in ischemic and non-ischemic kidneys, and upregulates that of APJ mRNA and protein in non-ischemic kidneys. Combination of puerarin and felodipine enhances the above-mentioned effects and shows no significant difference versus the combination of felodipine and captopril. The results suggest that puerarin regulates blood pressure and protects target organ through apelin/APJ pathway and that puerarin has synergetic effects with CCB.

Animals ; Antihypertensive Agents ; pharmacology ; Apelin ; Apelin Receptors ; Blotting, Western ; Captopril ; pharmacology ; Drug Synergism ; Felodipine ; pharmacology ; Gene Expression ; drug effects ; Hypertension, Renovascular ; genetics ; metabolism ; Intercellular Signaling Peptides and Proteins ; genetics ; metabolism ; Ischemia ; Isoflavones ; pharmacology ; Kidney ; blood supply ; drug effects ; metabolism ; Male ; RNA, Messenger ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptors, G-Protein-Coupled ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Vasodilator Agents ; pharmacology

To investigate the effect of losartan on the axis of prolylcarboxypeptidase (PRCP)--kallikrein of the two-kidney, one-clipped (2K1C) hypertensives rats, and explore the novel protection mechanism of losartan on the kidney. Sprague-Dawley (SD) rats were used to develop the 2K1C hypertensive rats. Then, the rats were treated with prazosin (5 mg x kg(-1) x d(-1)) or losartan (5, 15 and 45 mg x kg(-1) x d(-1)) or vehicle, separately. At the same time, the blood pressures were observed. After treated for four weeks, the ratio of right kidney weight and body weight, the change of glomerular morphology, and K+, Na+, creatinine and blood urea nitrogen (BUN) of the serum were used for evaluation of kidney. The expressions of PRCP mRNA in the kidneys were determined by RT-PCR. The protein levels of PRCP, tissue kallikrein, plasma kallikrein, TGF-beta1 in kidney or plasma were measured by Western blotting. Results showed that the changes of body weight and kidney weight ratio, glomerular fibrosis degree and the biochemistrical index of serum induced by hypertension were relieved when the hypertensive rats treated with losartan for four weeks. Meanwhile, treatment of losartan also significantly decreased expression of TGF-beta1 and increased expressions of PRCP, plasma kallikrein and tissue kallikrein. The protective effects of losartan on the kidney of 2K1C hypertensive rats are activation of the axis of PRCP-kallikrein and reducing the expression of TGF-beta1.
Animals ; Antihypertensive Agents ; pharmacology ; Blood Pressure ; drug effects ; Carboxypeptidases ; genetics ; metabolism ; Hypertension, Renovascular ; metabolism ; pathology ; physiopathology ; Kallikreins ; blood ; metabolism ; Kidney ; metabolism ; pathology ; Kidney Glomerulus ; pathology ; Losartan ; pharmacology ; Male ; Organ Size ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Transforming Growth Factor beta1 ; blood ; metabolism

OBJECTIVETo investigate the effect of losartan on prostatic hyperplasia in spontaneous hypertension rats (SHRs) and its pathophysiological mechanism.

METHODSWe randomly divided 36 male SHRs into three groups of equal number to be treated intragastrically with high-dose losartan (30 mg per kg per d), low-dose losartan (15 mg per kg per d) and distilled water (control group). After 6 weeks of intervention, we measured the body weight and tail artery blood pressure of the rats and compared them with the baseline data. We collected blood from the heart for determination of the levels of serum angiotensin II (Ang II), insulin-like growth factor-1 (IGF-1) and interleukin-6 (IL-6) by enzyme-linked immunosorbent assay (ELISA), and harvested their prostates for measurement of their weight, observation of the tissue ultrastructures under the electron microscope and detection of the expression of endothelial nitric oxide synthase (eNOS) in the prostate tissue by immunohistochemistry.

RESULTSCompared with the control group, the low- and high-dose losartan groups showed significant decreases in systolic blood pressure ([203.75 +/- 10.28] vs [184.54 +/- 16.90] mmHg, P = 0.013; [203.75 +/- 10.28] vs [166.88 +/- 14.74] mmHg, P = 0.001) and diastolic blood pressure ([151.58 +/- 9.96] vs [136.71 +/- 14.28] mmHg, P = 0.022; [151.58 +/- 9.96] vs [122.71 +/- 11.56] mmHg, P < 0.001) of the lower tail artery after treatment, as well as in the prostate weight ([0.73 +/- 0.08] vs [0.64 +/- 0.10] mg, P = 0.011; [0.73 +/- 0.08 ] vs [0.50 +/- 0.17] mg, P < 0.001). Electron microscopy revealed edema of the basal and columnar epithelial cells, concentrated and marginated heterochromatin and widened nuclear gap of interstitial fibroblast nuclei, and reduced mitochondria and endoplasmic reticula in the low-dose losartan group, and even more obvious in the high-dose group. The level of serum Ang II was remarkably higher in the low- and high-dose losartan groups than in the control ([61.32 +/- 2.49] vs [54.85 +/- 7.20] pg/ml, P = 0.021; [65.49 +/- 6.78] vs [54.85 +/- 7.20] pg/ml, P < 0.001]) , that of serum IGF-1 was lower in high-dose losartan than in the control group ([1.50 +/- 0.11] vs [1.60 +/- 0.10] ng/ml, P = 0.03), but the serum IL-6 levels exhibited no significant differences among the three groups. The expression of eNOS in the prostate tissue was significantly higher in the losartan groups than in the controls (P = 0.022), even higher in the high-dose than in the low-dose group.

CONCLUSIONLosartan can suppress the progression of prostate hyperplasia in spontaneous hypertension rats by inhibiting RAS, IGF-1 and angiogenesis.

Angiotensin II ; blood ; Animals ; Antihypertensive Agents ; pharmacology ; therapeutic use ; Hypertension ; drug therapy ; metabolism ; pathology ; Insulin-Like Growth Factor I ; metabolism ; Interleukin-6 ; blood ; Losartan ; pharmacology ; therapeutic use ; Male ; Nitric Oxide Synthase Type III ; metabolism ; Prostate ; drug effects ; metabolism ; pathology ; Prostatic Hyperplasia ; drug therapy ; metabolism ; pathology ; Rats ; Rats, Inbred SHR

BACKGROUNDAngiogenesis occurs commonly in various physiological and pathological processes. Improving blood supply through promoting angiogenesis is a novel approach for treating ischemic diseases. Angiotensin II type 1 receptor blockers (ARBs) dominate the management of hypertension, but evidence of their role in angiogenesis is contradictory. Here we explored the angiogenic effects of ARBs through characterizing gene expression of the human umbilical vein endothelial cell line EA.hy926 exposed to irbesartan.

METHODSThe human umbilical vein endothelial cell line EA.hy926 was grown for 72 hours after treatment with different concentrations of irbesartan. The cell proliferative capacity was assessed by CCK8 assay at 24, 48 and 72 hours. Gene expression levels in EA.hy926 cells responding to irbesartan were measured under optimal proliferation conditions by microarray analysis using Affymetrix U133 plus 2.0. The differential expression of genes involved in angiogenesis was identified through cluster analysis of the resulting microarray data. Quantitative RT-PCR and Western blotting analyses were used to validate differential gene expression related to the angiogenesis process.

RESULTSIn the 10(-4), 10(-5), 10(-6) mol/L treatment groups, cell proliferation studies revealed significantly increased proliferation in EA.hy926 cells after 24 hours of irbesartan treatment. However, after 48 and 72 hours of treatment with different concentrations of irbesartan, there was no significant difference in cell proliferation observed in any treatment group. We selected the group stimulated with irbersartan at a concentration of 10(-6) mol/L for microarray experiments. Statistical analysis of the microarray data resulted in the identification of 56 gene transcripts whose expression patterns were significantly correlated, negatively or positively, with irbesartan treatment. Cluster analysis showed that these genes were involved in angiogenesis, extracellular stimulus, binding reactions and skeletal system morphogenesis. Of these 56 genes we identified seven genes (VEGF, KDR, PTGS2, PLXND1, ROBO4, LMO2, and COL5A1) involved in the angiogenesis process. qRT-PCR analysis of these genes confirmed the microarray results. Protein expression of three VEGF pathway genes (VEGF, KDR, and PTGS2) was further confirmed by Western blotting.

CONCLUSIONSOur study showed that irbesartan may induce angiogenic effects in vascular endothelial cells. It suggested that the mechanism of angiogenic effects of ARBs might be attributed to the signaling cascade from angiotensin receptors in the VEGF pathway. It also provided evidence indicating that ARBs could be used as a novel therapeutic approach to treat chronic ischemic heart disease as well as anti-hypertensive agents.

Angiotensin II Type 1 Receptor Blockers ; pharmacology ; Antihypertensive Agents ; pharmacology ; Biphenyl Compounds ; pharmacology ; therapeutic use ; Cell Proliferation ; drug effects ; Cells, Cultured ; Endothelial Cells ; drug effects ; metabolism ; Gene Expression Profiling ; Humans ; Myocardial Ischemia ; drug therapy ; Neovascularization, Physiologic ; drug effects ; Tetrazoles ; pharmacology ; therapeutic use