Effects of Ca^(2+) channel blockers on store-operated Ca^(2+) channel currents of Kupffer cells after hepatic ischemia/reperfusion injury in rats

瞄准：学习肝的 ischemia/reperfusion ( I/R )的效果操作店的钙隧道( SOC )上的损害水流(我( SOC ))在刚孤立的老鼠 Kupffer ， Ca (2+)的房间，和效果隧道堵住 ers ， 2-aminoethoxydiphenyl 硼酸盐( 2-APB )， SK 和 F96365 ， econazole 和 miconazole ，在上我( SOC )在在肝的 I/R 损害以后的孤立的老鼠 Kupffer 房间。方法：老鼠的模型肝的 I/R 损害被建立。整个房间的斑夹钳技术被执行调查 2-APB， SK 和 F96365 的效果， econazole 和 miconazole 在上我(SOC ) 在孤立的老鼠 Kupffer 房间在以后肝我 /R 损害。结果：I/R 损害显著地增加了我(SOC ) 从 -80.4 +/- 25.2pA 到 -159.5 +/- 34.5pA ((b) P 【 0.01， n = 30 ) 。 2-APB ( 20 ， 40 ， 60 ， 80 ， 100 micromol/L )， SK 和 F96365 ( 5 ， 10 ， 20 ， 40 ， 50 micromol/L )， econazole ( 0.1 ， 0.3 ， 1 ， 3 ， 10 micromol/L )并且 miconazole ( 0.1 ， 0.3 ， 1 ， 3 ， 10 micromol/L )禁止我( SOC )以有 37.41 micromol/L 的 IC50 的一种集中依赖者方式( n = 8 )， 5.89 micromol/L ( n = 11 )， 0.21 micromol/L ( n = 13 )，并且 0.28 micromol/L ( n = 10 )。山峰价值(SOC ) 我被块 ers 在不同集中，而是反向的潜力在 I-V 关系中减少(SOC ) 我没被转变。结论：SOC 在肝的 I/R 损害期间是为 Ca (2+) 的流入的主要隧道。钙隧道块 ers， 2-APB， SK 和 F96365， econazole 和 miconazole，在 I/R 损害上有显然保护的效果，可能由禁止我(SOC ) 在 Kupffer 房间并且阻止 Kupffer 房间的激活。

Isoprenylated Flavonoids as Cav3.1 Low Voltage-Gated Ca^(2+)Channel Inhibitors from Salvia digitaloides

Saldigones A-C(1,3,4),three new isoprenylated flavonoids with diverse flavanone,pterocarpan,and isoflavanone architec-tures,were characterized from the roots of Salvia digitaloides,together with a known isoprenylated flavanone(2).Notably,it’s the first report of isoprenylated flavonoids from Salvia species.The structures of these isolates were elucidated by extensive spectroscopic analysis.All of the compounds were evaluated for their activities on Cav3.1 low voltage-gated Ca^(2+)channel(LVGCC),of which 2 strongly and dose-dependently inhibited Cav3.1 peak current.

New insight into Ca^(2+)-permeable channel in plant immunity

Calcium ions(Ca^(2+)) are crucial intracellular second messengers in eukaryotic cells. Upon pathogen perception, plants generate a transient and rapid increase in cytoplasmic Ca^(2+)levels, which is subsequently decoded by Ca^(2+)sensors and effectors to activate downstream immune responses. The elevation of cytosolic Ca^(2+)is commonly attributed to Ca^(2+)influx mediated by plasma membranelocalized Ca^(2+)–permeable channels. However, the contribution of Ca^(2+)release triggered by intracellular Ca^(2+)-permeable channels in shaping Ca^(2+)signaling associated with plant immunity remains poorly understood. This review discusses recent advances in understanding the mechanism underlying the shaping of Ca^(2+)signatures upon the activation of immune receptors, with particular emphasis on the identification of intracellular immune receptors as non-canonical Ca^(2+)-permeable channels. We also discuss the involvement of Ca^(2+)release from the endoplasmic reticulum in generating Ca^(2+)signaling during plant immunity.

Roles of Na^+/Ca^(2+) exchanger 1 in digestive system physiology and pathophysiology

The Na^+/Ca^(2+) exchanger(NCX) protein family is a part of the cation/Ca^(2+) exchanger superfamily and participates in the regulation of cellular Ca^(2+) homeostasis. NCX1, the most important subtype in the NCX family, is expressed widely in various organs and tissues in mammals and plays an especially important role in the physiological and pathological processes of nerves and the cardiovascular system. In the past few years, the function of NCX1 in the digestive system has received increasing attention; NCX1 not only participates in the healing process of gastric ulcer and gastric mucosal injury but also mediates the development of digestive cancer, acute pancreatitis, and intestinal absorption.This review aims to explore the roles of NCX1 in digestive system physiology and pathophysiology in order to guide clinical treatments.

Diabetes and inflammatory diseases:An overview from the perspective of Ca^(2+)/3'-5'-cyclic adenosine monophosphate signaling

A large amount of evidence has supported a clinical link between diabetes and inflammatory diseases,e.g.,cancer,dementia,and hypertension.In addition,it is also suggested that dysregulations related to Ca^(2+)signaling could link these diseases,in addition to 3'-5'-cyclic adenosine monophosphate(cAMP)signaling pathways.Thus,revealing this interplay between diabetes and inflammatory diseases may provide novel insights into the pathogenesis of these diseases.Publications involving signaling pathways related to Ca^(2+)and cAMP,inflammation,diabetes,dementia,cancer,and hypertension(alone or combined)were collected by searching PubMed and EMBASE.Both signaling pathways,Ca^(2+)and cAMP signaling,control the release of neurotransmitters and hormones,in addition to neurodegeneration,and tumor growth.Furthermore,there is a clear relationship between Ca^(2+)signaling,e.g.,increased Ca^(2+)signals,and inflammatory responses.cAMP also regulates pro-and anti-inflammatory responses.Due to the experience of our group in this field,this article discusses the role of Ca^(2+)and cAMP signaling in the correlation between diabetes and inflammatory diseases,including its pharmacological implications.As a novelty,this article also includes:(1)A timeline of the major events in Ca^(2+)/cAMP signaling;and(2)As coronavirus disease 2019(COVID-19)is an emerging and rapidly evolving situation,this article also discusses recent reports on the role of Ca^(2+)channel blockers for preventing Ca^(2+)signaling disruption due to COVID-19,including the correlation between COVID-19 and diabetes.

Tityus serrulatus venom and its toxins Ts1 and Ts5 increase cytosolic Ca^(2+)concentration in isolated vascular smooth muscle cells

Voltage-gated Na+ channel (Nav channel) scorpion toxins are classified as α- and β-neurotoxins. Ts5 (α-neurotoxin) and Ts1 (β-neurotoxin) from Tityus serrulatus venom (TsV) interact with Nav channels, increasing Na+ influx and activating voltage-dependent Ca2+ channels. This study aimed to investigate the effect of TsV, Ts1 and Ts5 on the cytosolic Ca2+ concentration ([Ca2+]C) in rat aortic smooth muscle cells. Toxins were isolated by ion exchange chromatography (Ts1) followed by RP-HPLC (Ts5). The rat aortic smooth muscle cells were isolated in Hanks buffer pH 7.4 and loaded with 5 μmol/L of Fura-2AM (45 minutes at 37℃), in order to measure [Ca2+]C by fluorescence of Fura-2/AM (ratio 340/380 nm). The fluorescence was measured in one single cell (excitation: 340 and 380 nm;emission: 510 nm). TsV (100 and 500 mg/mL) and its toxins Ts1 and Ts5 (50 and 100 mg/mL each) led to a concentration-dependent increase in [Ca2+]C. Tetrodotoxin (1 mmol/L), a Nav channel blocker, and verapamil (1 mmol/L), a voltage-operated Ca2+ channel blocker, inhibited the increase in [Ca2+]C induced by TsV (500 mg/mL). In conclusion, TsV and its toxins induce a concentration-dependent increase in [Ca2+]C that probably occurs through interaction with Nav channels, thus inducing depolarization and consequent Ca2+ influx. This assumption is based on the fact that this effect is inhibited by tetrodotoxin and verapamil, showing a direct action of TsV toxins on aorta smooth muscle cells.

Domesticated HERV-W env contributes to the activation of the small conductance Ca^(2+)-activated K^(+)type 2 channels via decreased 5-HT4 receptor in recent-onset schizophrenia

The human endogenous retroviruses type W family envelope(HERV-W env)gene is located on chromosome 7q21-22.Our previous studies show that HERV-W env is elevated in schizophrenia and HERV-W env can increase cal-cium influx.Additionally,the 5-HTergie system and particularly 5-hydroxytryptamine(5-HT)receptors play a prominent role in the pathogenesis and treatment of schizophrenia.5-hydroxytryptamine receptor 4(5-HT4R)agonist can block calcium channels.However,the underlying relationship between HERV-W env and 5-HT4R in the etiology of schizophrenia has not been revealed.Here,we used enzyme-linked immunosorbent assay to detect the concentration of HERV-W env and 5-HT4R in the plasma of patients with schizophrenia and we found that there were decreased levels of 5-HT4R and a negative correlation between 5-HT4R and HERV-W env in schizophrenia.Overexpression of HERV-W env decreased the transcription and protein levels of 5-HT4R but increased small conductance Ca^(2+)-activated K^(+)type 2 channels(SK2)expression levels.Further studies revealed that HERV-w env could interact with 5-HT4R.Additionally,luciferase assay showed that an essential region(-364 to-176 from the transcription start site)in the SK2 promoter was required for HERV-W env-induced SK2 expression.Importantly,5-HT4R participated in the regulation of SK2 expression and promoter activity.Electrophysiological recordings suggested that HERV-Wenv could increase SK2 channel currents and the increase of SK2 currents was inhibited by 5-HT4R.In condusion,HERV-W env could activate SK2 channels via decreased 5-HT4R,which might exhibit a novel mechanism for HERV-Wenv to influence neuronal activity in schizophrenia.

Diabetes-induced changes in cardiac voltage-gated ion channels

Diabetes mellitus affects the heart through various mechanisms such as microvascular defects,metabolic abnormalities,autonomic dysfunction and incompatible immune response.Furthermore,it can also cause functional and structural changes in the myocardium by a disease known as diabetic cardiomyopathy(DCM)in the absence of coronary artery disease.As DCM progresses it causes electrical remodeling of the heart,left ventricular dysfunction and heart failure.Electrophysiological changes in the diabetic heart contribute significantly to the incidence of arrhythmias and sudden cardiac death in diabetes mellitus patients.In recent studies,significant changes in repolarizing K+currents,Na+currents and L-type Ca^(2+)currents along with impaired Ca^(2+ )homeostasis and defective contractile function have been identified in the diabetic heart.In addition,insulin levels and other trophic factors change significantly to maintain the ionic channel expression in diabetic patients.There are many diagnostic tools and management options for DCM,but it is difficult to detect its development and to effectively prevent its progress.In this review,diabetes-associated alterations in voltage-sensitive cardiac ion channels are comprehensively assessed to understand their potential role in the pathophysiology and pathogenesis of DCM.

Calcium channels and their role in regenerative medicine

Stem cells hold indefinite self-renewable capability that can be differentiated into all desired cell types.Based on their plasticity potential,they are divided into totipotent(morula stage cells),pluripotent(embryonic stem cells),multipotent(hematopoietic stem cells,multipotent adult progenitor stem cells,and mesenchymal stem cells[MSCs]),and unipotent(progenitor cells that differentiate into a single lineage)cells.Though bone marrow is the primary source of multipotent stem cells in adults,other tissues such as adipose tissues,placenta,amniotic fluid,umbilical cord blood,periodontal ligament,and dental pulp also harbor stem cells that can be used for regenerative therapy.In addition,induced pluripotent stem cells also exhibit fundamental properties of self-renewal and differentiation into specialized cells,and thus could be another source for regenerative medicine.Several diseases including neurodegenerative diseases,cardiovascular diseases,autoimmune diseases,virus infection(also coronavirus disease 2019)have limited success with conventional medicine,and stem cell transplantation is assumed to be the best therapy to treat these disorders.Importantly,MSCs,are by far the best for regenerative medicine due to their limited immune modulation and adequate tissue repair.Moreover,MSCs have the potential to migrate towards the damaged area,which is regulated by various factors and signaling processes.Recent studies have shown that extracellular calcium(Ca^(2+))promotes the proliferation of MSCs,and thus can assist in transplantation therapy.Ca^(2+)signaling is a highly adaptable intracellular signal that contains several components such as cell-surface receptors,Ca^(2+)channels/pumps/exchangers,Ca^(2+)buffers,and Ca^(2+)sensors,which together are essential for the appropriate functioning of stem cells and thus modulate their proliferative and regenerative capacity,which will be discussed in this review.

The Ca^(2+)-activated chloride channel ANO1/TMEM16A:An emerging therapeutic target for epithelium-originated diseases?

Anoctamin 1(ANO1) or TMEM16 A gene encodes a member of Ca^(2+) activated Cl^(-) channels(CaCCs) that are critical for physiological functions,such as epithelial secretion,smooth muscle contraction and sensory signal transduction.The attraction and interest in ANO1/TMEM16 A arise from a decade long investigations that abnormal expression or dysfunction of ANO1 is involved in many pathological phenotypes and diseases,including asthma,neuropathic pain,hypertension and cancer.However,the lack of specific modulators of ANO1 has impeded the efforts to validate ANO1 as a therapeutic target.This review focuses on the recent progress made in understanding of the pathophysiological functions of CaCC ANO1 and the current modulators used as pharmacological tools,hopefully illustrating a broad spectrum of ANO1 channelopathy and a path forward for this target validation.

NADase and now Ca^(2+) channel, what else to learn about plant NLRs?

Plant intracellular immune receptors known as NLR(Nucleotide-binding Leucine-rich repeat,NB-LRR)proteins confer resistance and cause cell death upon recognition of cognate effector proteins from pathogens.Plant NLRs contain a variable N-terminal domain:a Toll/interleukin-1 receptor(TIR)domain or a coiled-coil(CC)domain or an RPW8(Resistance to Powdery Mildew 8)-like CC(CCR)domain.TIR-NLR,CC-NLR and CCR-NLR are known as TNL,CNL and RNL,respectively.TNLs and CNLs recognize pathogen effectors to activate cell death and defense responses,thus are regarded as sensor NLRs.RNLs are required downstream of TNLs to activate cell death and defense responses,thus are regarded as helper NLRs.Previous studies show that some TNLs form tetrameric resistosome as NAD+cleaving enzymes to transduce signal,while some CNLs form pentameric resistosome with undefined biochemical function.Two recent breakthrough studies show that activated CNL and RNL function as Ca2+channel to cause cell death and defense responses and provide a completely new insight into the downstream signaling events of CNL and TNL pathways.

钙拮抗剂在治疗高血压中的现状及前景

1钙拮抗剂（Calcium Channel Blocker，CCB）的基本概念 CCB（Calcium Channel Blocker）是指药物选择性地阻断细胞膜上的钙离子通道（慢钙通道）使细胞内结合Ca^2＋释放有活性的游离Ca^2＋下降。一方面使胞内肌浆网释放Ca^2＋下降，同时减少Ca^2＋与调钙素相结合，使肌球蛋白氢键激酶（MLCR）活化，肌球蛋白与肌动蛋白相互作用引起的收缩作用减弱。

Sources of calcium in agonist-induced contraction of rat distal colon smooth muscle in vitro

AIM: To study the origin of calcium necessary for agonist-induced contraction of the distal colon in rats.METHODS: The change in intracellular calcium concentration ([Ca2+]i) evoked by elevating external Ca2+ was detected by fura 2/AM fluorescence. Contractile activity was measured with a force displacement transducer. Tension was continuously monitored and recorded using a Powerlab 4/25T data acquisition system with an ML110 bridge bioelectric physiographic amplifier.RESULTS: Store depletion induced Ca2+ influx had an effect on [Ca2+]i. In nominally Ca2+-free medium, the sarco-endoplasmic reticulum Ca2+-ATPase inhibitor thapsigargin (1 μmol/L) increased [Ca2+]i from 68 to 241 nmol/L, and to 458 (P < 0.01) and 1006 nmol/L (P < 0.01), respectively, when 1.5 mmol/L and 3.0 mmol/L extracellular Ca2+ was reintroduced. Furthermore, the change in [Ca2+]i was observed with verapamil (5 μmol/L), La3+ (1 mmol/L) or KCl (40 mmol/L) in the bathing solution. These channels were sensitive to La3+ (P < 0.01), insensitive to verapamil, and voltage independent. In isolated distal colons we found that in normal Krebs solution, contraction induced by acetylcholine (ACh) was partially inhibited by verapamil, and the inhibitory rate was 41% (P < 0.05). On the other hand, in Ca2+-free Krebs solution, ACh induced transient contraction due to Ca2+ release from the intracellular stores. The transient contraction lasted until the Ca2+ store was depleted. Restoration of extracellular Ca2+ in the presence of atropine produced contraction, mainly due to Ca2+ influx. Such contraction was not inhibited by verapamil, but was decreased by La3+ (50 μmol/L) from 0.96 to 0.72 g (P < 0.01). CONCLUSION: The predominant source of activator Ca2+ for the contractile response to agonist is extracellular Ca2+, and intracellular Ca2+ has little role to play in mediating excitation-contraction coupling by agonists in rat distal colon smooth muscle in vitro. The influx of extracellular Ca2+ is mainly mediated through voltage-, receptor- and store-operated Ca2+ channels, which can be used as an alternative to develop new drugs targeted on the dysfunction of digestive tract motility.

L-type Calcium Channels are Involved in Iron-induced Neurotoxicity in Primary Cultured Ventral Mesencephalon Neurons of Rats

In the present study,we investigated the mechanisms underlying the mediation of iron transport by Ltype Ca^2+ channels(LTCCs)in primary cultured ventral mesencephalon(VM)neurons from rats.We found that cotreatment with 100 lmol/L FeSO4 and MPP^+(1-methyl-4-phenylpyridinium)significantly increased the production of intracellular reactive oxygen species,decreased the mitochondrial transmembrane potential and increased the caspase-3 activation compared to MPP^+ treatment alone.Co-treatment with 500 lmol/L CaCl2 further aggravated the FeSO4-induced neurotoxicity in MPP^+-treated VM neurons.Co-treatment with 10 lmol/L isradipine,an LTCC blocker,alleviated the neurotoxicity induced by co-application of FeSO4 and FeSO4/CaCl2.Further studies indicated that MPP^+treatment accelerated the iron influx into VM neurons.In addition,FeSO4 treatment significantly increased the intracellular Ca^2+ concentration.These effects were blocked by isradipine.These results suggest that elevated extracellular Ca^2+ aggravates ironinduced neurotoxicity.LTCCs mediate iron transport in dopaminergic neurons and this,in turn,results in elevated intracellular Ca^2+ and further aggravates iron-induced neurotoxicity.

Efficacy on rabbits with arrhythmia: needling acupoint of Neiguan(PC6) at shallow or deep depth, and retaining needles for 10, 20, or 30 min

OBJECTIVE:To compare the effects of Neiguan(PC6)acupuncture at different depths and retention time on arrhythmia duration,myocardial tissue morphology,mRNA expression level of L-type calcium channelα1C subunit and Ca^(2+)-Mg^(2+)-At Pase activity in tachirrhythmia model of rabbits.METHODS:The tachyarrhythmia model was made by intravenous injection of barium chloride into the ears of rabbits.A total of 56 healthy adult male New Zealand big-eared white rabbits,apply the random number table method,divided into normal control group(group A),model group(group B),shallow needling Neiguan(PC6)10 min group(group C),shallow needling Neiguan(PC6)20 min group(group D),shallow needling Neiguan(PC6)30 min group(group E),deep needling Neiguan(PC6)10 min group(group F),deep needling Neiguan(PC6)20 min group(group G),deep needling Neiguan(PC6)30 min group(group H),7 animals in each group.Electrocardiograms were used to collect the duration of arrhythmia;hematoxylin-eosin staining method was performed on myocardial tissue,RT-PCR tested the expression ofα1C subunit mRNA,and the activity of Ca^(2+)-Mg^(2+)-ATPase were quantified by phosphorus determination method.RESULTS:The duration of arrhythmia in each acupuncture treatment group was shortened to varying degrees.Compare to the model group,the tissue damage from barium chloride inducing was improved in the acupuncture group.Compared to the model group,except for group E,most treatment groups had varying degrees of improvement with significantly down-regulated L-type calcium channelα1C subunit mRNA expressions level and increased Ca^(2+)-Mg^(2+)-ATPase activity.CONCLUSIONS:The effect of acupuncture at Neiguan(PC6)with different depths and retention time can reduce the duration of arrhythmia induced by barium chloride relatively,improve the induced pathological changes,down regulate L-type calcium channelα1C subunit mRNA expressions level and increase Ca^(2+)-Mg^(2+)-ATPase activity.Both the shallow and deep tissues of Neiguan(PC6)may be involved in transmitting acupuncture information.There is an optimal induction period for shallow needling at Neiguan(PC6)to reach the best therapeutic effect.

Abietane derived diterpenoids as Ca_(v)3.1 antagonists from Salvia digitaloides

Nineteen diterpenoids, including saldigitin A(1) bearing an unprecedented 10-methylated 6/7/6 carbon ring system, two new icetexanes(2, 3), and two new nor-abietanes(5, 6) were characterized from the roots of Salvia digitaloides. Their structures were elucidated by the analysis of the spectroscopic data,X-ray crystallography, and TDDFT calculations of ECD spectra. The novel architecture of 1 should be biogenetically derived through the cleavage and re-cyclization of the B/C rings from the normal abietane skeleton. Biologically, 1–5 exhibited noticeable inhibitions on Ca_(v)3.1 low voltage-gated Ca2+channel(LVGCC), with IC50values in the range of 3.43–11.70 μmol/L. They are the first example of diterpenoids with 6/7/6 carbon rings system as Ca_(v)3.1 antagonists.

Chenopodium ambrosioides induces an endothelium-dependent relaxation of rat isolated aorta

Objective: This study aims to evaluate the vasodilatory effect of Chenopodium ambrosioides on the isolated rat aorta, and to explore its mechanism of action.Methods: The vasorelaxant effect and the mode of action of various extracts from the leaves of C. ambrosioides were evaluated on thoracic aortic rings isolated from Wistar rats. In addition, ethyl acetate and methanol fractions were analyzed, using thin-layer chromatography and high-performance liquid chromatography techniques, for their polyphenolic content.Results: The various active extracts of C. ambrosioides at four concentrations(10^(-3), 10^(-2), 10^(-1) and 1 mg/mL) relaxed the contraction elicited by phenylephrine, in a concentration-dependent manner.This effect seems to be endothelium-dependent, since the vasodilatory effect was entirely absent in denuded aortic rings. The vasorelaxant effect of the methanol fraction(MF) of C. ambrosioides at 1 mg/mL was also inhibited by atropine and tetraethylammonium. This effect remained unchanged by Nx-nitro-L-arginine methyl ester hydrochloride and glibenclamide. The preliminary phytochemical analysis showed that the leaves of C. ambrosioides are rich in phenolic and flavonoid derivatives.Conclusion: These results suggest that the MF of C. ambrosioides produces an endothelium-dependent relaxation of the isolated rat aorta, which is thought to be mediated mainly through stimulation of the muscarinic receptors, and probably involving the opening of Ca^(2+)-activated potassium channels.