Effect of Electroacupuncture on Renal CaM/NO Pathway in Dahl Rats with Prehypertension / 上海针灸杂志

Objective To investigate the effect of electroacupuncture on renal CaM-eNOS-NO signal pathway in Dahl salt-sensitive rats with prehypertension.Methods Thirty 7-week-old male Dahl salt-sensitive rats (DS) were allocated,using a random number table,to model,acupuncture and non-meridian-acupoint groups.Ten 7-week-old male Dahl salt-resistant rats (DR) were used as a blank group.The rats were fed in a SPF animal experiment center.An 8％ NaC1 high salt diet was provided after 1-week adaptive feeding.During the period,rat blood pressure was monitored using an intelligent noninvasive sphygmomanometer.A rat model of prehypertension was successfully made if rat blood pressure rose to 120～ 139/80～89 mmHg after 12 days.At that time,a high salt diet was stopped and a normal diet was provided.The blank and model groups received 15-minute regular fixation and no treatment.The acupuncture group received electroacupuncture at bilateral Quchi and Zusanli.The non-meridianacupoint group received electroacupuncture at fixed control points selected between 10 and 15 mm above bilateral iliac crests 20 mm lateral to the midline.Treatment was given once daily,6 times a week,for five consecutive weeks.The left rat kidney was taken.CaM and eNOS mRNA expressions were determined by quantitative fluorescence PCR.eNOS was quantified and located by western blot and immunohistochemical method.NO content was measured by ELISA.Results As compared with the blank group,CaM and eNOS mRNA expressions,eNOS protein content and NO content decreased significantly in the model group (all P＜0.05).As compared with the model group,CaM and eNOS mRNA expressions,eNOS protein content and NO content increased significantly in the acupuncture group (all P＜0.05).As compared with the model group,CaM expression increased significantly (P＜0.05) but eNOS mRNA expression and NO content had no statistically significant differences (P＞0.05) in the non-meridian-acupoint group.Conclusion The renoprotective effect of electroacupuncture at Quchi and Zusanli may be related to upregulating renal CaM-eNOS-NO signal pathway in DS rats with prehypertension.

Salt-induced epithelial-to-mesenchymal transition in Dahl salt-sensitive rats is dependent on elevated blood pressure

Dietary salt intake has been linked to hypertension and cardiovascular disease. Accumulating evidence has indicated that salt-sensitive individuals on high salt intake are more likely to develop renal fibrosis. Epithelial-to-mesenchymal transition (EMT) participates in the development and progression of renal fibrosis in humans and animals. The objective of this study was to investigate the impact of a high-salt diet on EMT in Dahl salt-sensitive (SS) rats. Twenty-four male SS and consomic SS-13BN rats were randomized to a normal diet or a high-salt diet. After 4 weeks, systolic blood pressure (SBP) and albuminuria were analyzed, and renal fibrosis was histopathologically evaluated. Tubular EMT was evaluated using immunohistochemistry and real-time PCR with E-cadherin and alpha smooth muscle actin (α-SMA). After 4 weeks, SBP and albuminuria were significantly increased in the SS high-salt group compared with the normal diet group. Dietary salt intake induced renal fibrosis and tubular EMT as identified by reduced expression of E-cadherin and enhanced expression of α-SMA in SS rats. Both blood pressure and renal interstitial fibrosis were negatively correlated with E-cadherin but positively correlated with α-SMA. Salt intake induced tubular EMT and renal injury in SS rats, and this relationship might depend on the increase in blood pressure.

The Effet of Nifedipine on the Blood Pressure, Water and Cation Balance of the Lens in Spontaneous Hypertensive Rats

In systemic hypertension, capillary resistance is highly elevated and' contractility of vascular smooth muscle is elevated. This is due to increased calcium uptake into the sarcoplasmic reticulum of the vascular smooth muscle. Recently, nifedipine, an antihypertensive medication which inhibits calcium uptake into the vascular smooth muscle is commonly used. It decreases the contractility of the vascular smooth muscle and causes the vessels to relax, which in turn lowers the blood pressure. In 1987, according to Rodriguez-Sargent et al. the increased incidence of cataract in Dahl-salt sensitive rats(DSR) was due to increasd water and sodium contents and decreased potassium content. In this investigative study on hypertension, the water, Sodium and potassium contents in Spontaneous Hypertensive Rats(SHR) were measured. After treatment with nifedipine in SHR, we observed decreased blood pressure along with the changes in water, sodium and potassium contents of the lenses. The following results were obtained from our experiments. 1. In normal SDR, The blood pressure did not decrease with nifedipine injection. 2. After 3-7 days of nifedipine injection bidaily, the blood pressure of SHR did not decrease. 3. After 2 weeks of nifedipine injection bidaily, the blood pressure of the SHR decreased slightly and after 4 weeks of nifedipine injection bidaily, the blood pressure of SHR decreased significantly. 4. Water and sodium contents of SHR were higher than that of SDR and the potassium content was similar to that of SDR. 5. The elevated water and sodium contents of SHR decreased along with decrease of blood pressure, and after 2 weeks of nifedipine injection, showed similar level as the contents of SDR lenses. 6. Potassium contents of SHR lenses showed no change were similar to SDR lines except the 4 weeks nifedipine injection group which showed higher potasslum contents.