复方鳖甲软肝方对家兔心室肌细胞钙通道的影响

目的:研究复方鳖甲软肝方对家兔单个心室肌细胞L-型钙通道(ICa-L)的电生理作用。方法:采用改良的中药血清药理学方法及全细胞膜片钳技术观察不同浓度的复方鳖甲软肝方药物血清干预心肌细胞后对心肌细胞ICa-L电流的影响。结果:含0.7 g/L和1.4 g/L的复方鳖甲软肝方药物血清使兔心室肌细胞ICa-L峰值电流密度(ICa-L m ax)由(6.90±0.52)pA/pF分别下降至(3.40±0.28)pA/pF和(2.30±0.18)pA/pF(P<0.01)。复方鳖甲软肝方使ICa-L的电流-电压曲线上移,但不改变其激活电位、电位峰值和反转电位,同时还抑制ICa-L的激活过程。结论:复方鳖甲软肝方对ICa-L具有浓度依赖性阻滞作用,这可能是其抗心肌纤维化的部分机制。

Comparative identification of Ca～(2+) channel expression in INS-1 and rat pancreatic β cells

AIM： To identify and compare the profile of Ca^2＋ channel subunit expression in INS-1 and rat pancreatic β cells.METHODS： The rat insulin-secreting INS-1 cell line was cultured in RPMI-1640 with Wistar rats employed as islet donors. Ca^2＋ channel subunit expression in INS-1 and isolated rat β cells were examined by reverse transcription polymerase chain reaction （RT-PCR）. Absolute real-time quantitative PCR was performed in a Bio-Rad iQ5 Gradient Real Time PCR system and the data analyzed using an iQ5 system to identify the expression level of the Ca^2＋ channel subunits. RESULTS： In INS-1 cells, the L-type Ca^2＋ channel 1C subunit had the highest expression level and the TPRM2 subunit had the second highest expression. In rat β cells, the TPRC4β subunit expression was dominant and the expression of the L-type lC subunit exceeded the 1D subunit expression about two-fold. This result agreed with other studies, confirming the important role of the L-type lC subunit in insulinsecreting cells, and suggested that non-voltage-operated Ca^2＋ channels may have an important role in biphasic insulin secretion. CONCLUSION： Twelve major Ca^2＋ channel subunit types were identified in INS-1 and rat β cells and significant differences were observed in the expression of certain subunits between these cells.

BEHAVIOR AND ACTIVITIES IN THE CENTRAL NERVOUS SYSTEM AFTER ACTIVATION OF L-TYPE CALCIUM CHANNELS IN MICE

The distribution of the immediate early gene c-fos expression in the mouse central nervous system after subcutaneous injection of Bay K 8644 was observed immunohistochemically. Half an hour after injection, cfos protein (FOS) was expressed in the piriform cortex, sensorimotor cortex, caudate putamen, thalamic paraventricular nucleus and striate cortex,etc. Intense FOS immunoreactive (FOS-ir) cells were seen during 2 ～ 4 h after injection. The restllts suggested that the distribution of FOS-ir ce1ls after subcutaneous injection of Bay K 8644 was coincldent with that of L-type calcium channels in the different areas of the CNS. After Bay K 8644 injection, mice appeared seizure-like behavior. The percentage of cells double-labelled by FOS and CaBP immunoreactivities in the observed regions was about 60. 2～72. 8% in CaBP-ir cells. It suggested that most CaBP-lr cells may have L-type calcium channels.

Effects of cilnidipine and L-type calcium channel blockers on renal functions in hypertensive patients: a meta-analysis of the randomized trials

In the present study, we aimed to evaluate the effects of cilnidipine and L-type calcium channel blockers（L-type CCBs） on renal function in hypertensive patients. The randomized controlled trials（RCTs） of cilnidipine and L-type CCBs on hypertension treatment were selected from Pubmed, Embase, Google Scholar, CNKI, Science Direct, Ebsco, Springer, Ovid, Cochrane Library, Medline, VIP and Wanfang databases（from the date of databases＇ establishment to September 2014）. Data were independently evaluated following the Jadad standard. The percentage changes of serum creatinine（SCr） value, urinary protein excretion（UPE）, urinary protein/creatinine ratio（UPCR） and estimated glomerular filtration rate（e GFR） pre- and post-treatment were extracted for the subsequent meta-analysis. The mean difference（MD） and the 95% confidence interval（95% CI） were determined using RevM an 5.3 software. A total of 10 RCTs of high quality were included and analyzed by fixedor random-effect models. The results indicated that UPE（MD = –36.59, 95% CI： –70.85, –2.33） or UPCR（MD = –46.56, 95% CI： –88.50, –4.62） was significantly reduced by cilnidipine compared with L-type CCBs. However, such significant difference was not detected in reduction of SCr（MD = 0.01, 95% CI： –2.97, 2.98） or eG FR（MD = 1.56, 95% CI： –0.19, 3.31）. Compared with L-type CCBs, cilnidipine was more effective in reducing proteinuria or preventing the proteinuria progression. In addition, we did not find significant differences in SCr and eG FR between the two groups.

Mechanism and effect of Shijueming (Concha Haliotidis) on serum calcium in spontaneously hypertensive rats

OBJECTIVE： To observe the impact of Shijueming （Concha Haliotidis） on spontaneously hypertensive rats via blood pressure, serum calcium, vascular smooth muscle membrane L-type calcium channel α1 C subunit （CaL-α1C）, plasma membrane calci- um-ATPase （PMCA） mRNA expression, and the L-type calcium channel in vascular smooth muscle cells. METHODS： Twelve-week-old male rats with sponta- neous hypertension were divided into three groups： a Shijueming （Concha Haliotidis） group （group 1）, a nifedipine group （group 2）, and a dis- tilled water group （group 3）. All were given a four-week treatment. Blood pressure and dissocia- tive serum calcium were examined before treat- ment. Blood pressure was taken every week during treatment. Atomic absorption spectrometry was used to examine dissociative serum calcium. Re-verse transcription-polymerase chain reaction was used to examine the expression of CaL-α1C and PM- CA1 mRNA. The patch clamp technique was used to examine the electrophysiological characteristics of the vascular smooth muscle cell calcium chan- nels. RESULTS： After treatment, blood pressure of the Shijueming （Concha Halioticlis） group lowered but not significantly （P〉0.05）. Blood pressure of the nifedipine group lowered significantly （P〈0.05）. Blood pressure of the distilled water group re- mained high. The concentration of serum calcium in the Shijueming （Concha Haliotidis） and the dis- tilled water groups lowered （P〈0.05）. Expression of CaL-α1C mRNA in the nifedipine group decreased compared with the distilled water group （P〈0.01）. There was the decreasing trend in the Shijueming （Concha Haliotidis） group, but it was not statistically significant. Shijueming （Concha Haliotidis） also had effects on the expression of PMCA1 mRNA but with- out statistical significance. However, there was a significant decreasing effect on vascular smooth muscle cell Ica-L flow. CONCLUSION： This study indicated that Shijuem- ing （Concha Haliotidis） could increase serum calci- um and decrease blood pressure. It may work by in- fluencing calcium channels, expression of PMCA1 mRNA, and regulating ion calcium channels and calcium-ATPase.