小檗碱对豚鼠心室肌细胞L—及T—型钙离子通道的影响

目的：研究小檗碱（Ｂｅｒ）对心室肌细胞钙通道的影响。方法：全细胞膜片箝技术，结果：Ｂｅｒ（１０，３０μｍｏｌ．Ｌ＾－１）使豚鼠心室细胞Ｌ－型钙流由１４００±２４７ｐＡ分别减至９７８±２０４ｐＡ及６１７±２３ｐＡ（ｎ＝５，Ｐ〈０．０５），抑制效应呈浓度依赖及非频率依赖，其电流－电压曲线的峰值下降，Ｂｅｒ（１０μｍｏｌ．Ｌ＾－１）使Ｌ－型钙流失活曲线的最大半激活电压由－２７．８ｍＶ变为－３４．２ｍＶ，     

IQ_(23)对豚鼠心室肌细胞钙通道和CHO H_(10)细胞异源表达的钙通道α_1亚单位的作用

应用膜片钳全细胞记录技术,观察了具有正性肌力作用的苄基异喹啉衍化物ＩＱ２３,即１－〔对甲氧苄基－２－（Ｎ－苄基,Ｎ－甲基）〕－６,７－二甲氧基异喹啉盐酸盐,对豚鼠心室肌分离细胞的Ｃａ２＋通道,以及ＣＨＯＨ１０细胞表达的Ｃａ２＋通道α１亚单位的作用．结果显示,当豚鼠心室肌细胞从保持电位（Ｖｈ）－５０ｍＶ除极至测试电位（Ｖｔ）０ｍＶ时,ＩＱ２３３,１０μｍｏｌ·Ｌ－１分别使Ｃａ２＋电流（ＩＣａ）由对照的（０．４７±０．２３）ｎＡ增至（０．５７±０．２３）和（０．７９±０．３１）ｎＡ（Ｐ＜０．０５）．在ＣＨＯＨ１０细胞Ｖｔ为２０ｍＶ时,ＩＱ２３１０μｍｏｌ·Ｌ－１电压依赖性的增强Ｂａ２＋电流（ＩＢａ）,ＩＢａ从（０．４５±０．１０）ｎＡ增至（０．６７±０．２０）ｎＡ（Ｖｈ＝－８０ｍＶ）,或从（０．４３±０．０８）ｎＡ增至（０．６０±０．１４）ｎＡ（Ｖｈ＝－４０ｍＶ）．ＩＱ２３１０和３０μｍｏｌ·Ｌ－１还分别使电流－电压曲线的峰值和失活曲线的半失活电位向负膜电位方向移动．实验结果表明,ＩＱ２３通过作用于通道的α１亚单位,对心肌Ｌ型Ｃａ２＋通道产生电压依赖性激动作用,此作用为其正性肌力效应提供了部分解释．     

超氧阴离子对培养的牛动脉平滑肌细胞内钙及收缩性的影响

目的研究超氧阴离子对牛主动脉平滑肌细胞内钙及收缩性的影响。方法采用Ｆｕｒａ－２测定牛肺动脉平滑肌细胞内钙及采用胶原凝胶实验方法分析平滑肌细胞的收缩性。结果超氧阴离子作用于平滑肌细胞后使ＡＴＰ（１０μｍｏｌ·Ｌ－１）诱导的细胞内钙浓度的增加从（２０６± １０） ｎｍｏｌ·Ｌ－１降到（１４７±１５） ｎｍｏｌ·Ｌ－１。 ５ ｍｉｎ内细胞内钙浓度增加的积分（∫　△［Ｃａ２＋］ｉ·ｄｔ）从（１２．２± ０．５）μｍｏｌ· Ｌ－１·ｓ－１降至（９．８± ０．８）μｍｏｌ·Ｌ－１·ｓ－１。ｔｈａｐｓｉｇａｒｇｉｎ在无钙溶液中诱导的细胞内钙浓度的增加不受超氧阴离子的影响,而在含钙的Ｋｒｅｂａ溶液中,超氧阴离子能使随后的钙释放激活的钙进入（△［Ｃａ２＋］ｉＣＲＡＣ）从（２７．３ ±１．０） ｎｍｏｌ·Ｌ－１降到（１３．５ ±１．０） ｎｍｏｌ·Ｌ－１。ＡＴＰ诱导的凝胶面积减少的百分比从２４％±５％降到 ７．４％ ±０．２％;在无钙 Ｋｒｅｂｓ溶液中,ｔｈａｐｓｉｇａｒｇｉｎ诱导的凝胶面积减少的百分比从 ３．５％± ０．６％降到－０．５％±０．７％。结论超氧阴离子通过影响平滑肌细胞的内钙动员而降低它的收缩性。     

Effects of berberine on L-and T-type calcium channels in guinea pig ventricular myocytes

目的：研究小檗碱（Ｂｅｒ）对心室肌细胞钙通道的影响．方法：全细胞膜片箝技术．结果：Ｂｅｒ（１０，３０μｍｏｌ·Ｌ－１）使豚鼠心室肌细胞Ｌ型钙流由１４００±２４７ｐＡ分别减至９７８±２０４ｐＡ及６１７±２３ｐＡ（ｎ＝５，Ｐ＜００５），抑制效应呈浓度依赖及非频率依赖，其电流－电压曲线的峰值下降．Ｂｅｒ（１０μｍｏｌ·Ｌ－１）使Ｌ型钙流失活曲线的最大半激活电压由－２７８ｍＶ变为－３４２ｍＶ，斜率因子由９２２变为１３０３，对激活曲线无影响．Ｂｅｒ（１０，３０μｍｏｌ·Ｌ－１）使Ｔ型钙流峰值由加药前的１５４±８０ｐＡ降至１０１±７８ｐＡ及４８±４５ｐＡ（ｎ＝８，Ｐ＜００５）．结论：Ｂｅｒ对Ｌ和Ｔ型钙通道均有抑制作用．     

四氢巴马汀对豚鼠心室肌细胞跨膜内向Ca^2＋电流

目的：研究四氢巴马汀（ＴＨＰ）对豚鼠心室肌细胞膜Ｃａ＾２＋通道的作用。方法：分离豚鼠心室肌细胞，利用膜片箝技术观察，记录心室肌细胞膜跨膜内向钙电流（１Ｃａ）结果：ＴＨＰ灌流５ｍｉｎ后明显抑制豚鼠心肌肌细胞内向１Ｃａ，其作用呈现剂量效应关系，并具有频率依赖性，０．１，１，１０μｍｏｌ．Ｌ＾－１的ＴＨＰ使１ｃａ从１．１５±０．２２，０．９１±０．１８，１．６０±０．４２ｎＡ（ｃｏｎｔｒｏｌ，ｎ＝５）分     

甲基莲心碱对心肌细胞I_(Na)、I_(Ca-L)及稳态外向K~+电流的影响

目的　为证明甲基莲心碱（ Ｎｅｆｅｒｉｎｅ, Ｎｅｆ） 对单个心肌细胞离子通道电流的影响及抗心律失常作用的离子通道机制。方法　采用全细胞记录膜片钳技术,记录了 Ｎｅｆ 对培养大鼠心室肌细胞钠电流（ Ｉ Ｎａ） 及豚鼠心室肌细胞动作电位、 Ｉ Ｎａ 、 Ｌ 型钙电流（ Ｉ Ｃａ Ｌ） 及稳态外向 Ｋ＋ 电流的影响。结果　 Ｎｅｆ ３０ ,１００ μｍｏｌ· Ｌ－ １ 明显抑制培养大鼠心室肌细胞 Ｉ Ｎａ ,分别从对照水平的（３４ ±０７） ｎ Ａ 降至（２１ ±０５） 和（０４ ±０２） ｎ Ａ。 Ｎｅｆ １０ μｍｏｌ· Ｌ－ １ 可降低豚鼠心室肌细胞动作电位振幅、静息电位,延长动作电位时程。 Ｎｅｆ １０ ,３０ μｍｏｌ· Ｌ－ １ 分别使豚鼠心室肌细胞 Ｉ Ｎａ 及 Ｉ Ｃａ Ｌ从给药前的（７９ ±２１） ｎ Ａ 和（６８９ ±２４３） ｐ Ａ 降至（４０ ±１４） 、（１３ ±０６） ｎ Ａ和（３７４ ±１７２） 、（１０９ ±６７） ｐ Ａ。 Ｎｅｆ １０ μｍｏｌ· Ｌ－ １ 还抑制 Ｉ Ｎａ 、稳态外向 Ｋ＋ 电流和 Ｉ Ｃａ Ｌ的 Ｉ Ｖ 曲线并使后者的峰值电流电位略右移。结论　 Ｎｅｆ 有钠、 Ｌ 型钙通道阻滞作用并抑制稳态外向 Ｋ＋ 电流,这些可解释     

延髓腹外侧头端注射莫索尼定对大鼠血压,心率和肾交感神经放电…

目的：观察延髓腹外侧头端（ＲＶＬＭ）注射莫索尼定（Ｍｏｘ）对麻醉大鼠血压（ＢＰ）、心率（ＨＲ）及肾交感神经放电（ＲＳＮＡ）的影响。方法：麻醉大鼠ＲＶＬＭ注射１μＬ Ｍｏｘ１，１０，１００μｍｏｌ·Ｌ＾－１，同步记录ＢＰ，ＨＲ及ＲＳＮＡ。结果：Ｍｏｘ１，１０，１００μｍｏｌ·Ｌ＾－１分别使ＢＰ从１３．９±１．０ｋＰａ降至１３．０±１．７ｋＰａ（Ｐ〈０．０５），１３．８±１．８ｋＰａ至１１．４±１．５     

N-甲基小檗胺对豚鼠单一心室肌细胞ATP敏感钾电流的影响

目的　研究Ｎ 甲基小檗胺对豚鼠单一心室肌细胞ＡＴＰ敏感钾电流的作用。方法　膜片钳制技术全细胞记录模式。结果　Ｎ 甲基小檗胺抑制心室肌细胞ＡＴＰ敏感钾电流（ＩＫＡＴＰ）且具浓度依赖关系。指令电位为０ｍＶ时,３种浓度Ｎ 甲基小檗胺（０－１,１,１０μｍｏｌ·Ｌ－１）可使ＩＫＡＴＰ分别由给药前的（０－４６±０－０９）ｎＡ,（０－４３±０－１５）ｎＡ和（０－４７±０－１０）ｎＡ减少至给药后的（０－３７±０－０７）ｎＡ（ｎ＝４,Ｐ＜０－０５）,（０－２９±０－１８）ｎＡ（ｎ＝５,Ｐ＜０－０５）和（０－２１±０－０７）ｎＡ（ｎ＝４,Ｐ＜０－０５）。其抑制率分别为１８－８１％±６－１６％（Ｐ＜０－０５）,４１－４７％±２４－０５％（Ｐ＜０－０５）和５５－００％±１２－９４％（Ｐ＜０－０５）。其它指令电位下的ＩＫＡＴＰ的改变也符合此趋势。结论　Ｎ 甲基小檗胺阻断豚鼠心肌细胞ＡＴＰ敏感Ｋ＋钾通道。     

粉防己碱对大鼠脑细胞内游离钙的影响

利用荧光钙指示剂Ｆｕｒａ－２／ＡＭ，测定脑细胞内游离钙的浓度，细胞内静息钙浓度为２２１±１８ｎｍｏｌ·Ｌ＾－１。Ｔｅｔ３０μｍｏｌ·Ｌ＾－１对细胞内静息钙无影响。Ｔｅｔ（１－１００μｍｏｌ·Ｌ＾－１）能抑制胞外高钾引起的胞内钙升高，其ＩＣ５０为８．２（９５％可信限为１．８９－３２．９０μｍｏｌ·Ｌ＾－１）。Ｔｅｔ３０μｍｏｌ·Ｌ＾－１可抑制去甲肾上腺素１０μｍｏｌ·Ｌ＾－１引起细胞内钙升高，其幅…     

粉防己碱对分离的豚鼠心室肌单细胞动作电位及钙通道电流的影响

用自行研制的膜片钳实验系统，研究粉防己碱对分离的豚鼠心室肌单细胞动作电位及钙电流的影响。在电流钳制方式下，给予脉宽３ｍｓ，０．５Ｈｚ电流刺激，引出单细胞动作电位，粉防己碱３０μｍｏｌ·Ｌ－１可使ＡＰＤ５０缩短７２．２％，ＡＰＤ９０缩短４４．０％，而静息电住，动作电位幅值无明显改变，在电压钳方式下，保持电位－４０ｍＶ，给予脉宽１５０ｍ５、０．５Ｈｚ去极化刺激可记录到Ｌ型钙通道电流，０．３～３００μｍｏｌ·Ｌ－１粉防己碱浓度依赖性地阻滞钙电流，ＩＣ５０＝１３．３μｍｏｌ·Ｌ－１．粉防己碱对钙通道的电流－电压关系无明显影响。     

酚妥拉明对豚鼠心室肌细胞L型钙电流及ATP敏感钾电流的抑制作用

目的：研究酚妥拉明对豚鼠凡肌细胞Ｌ－型钙电流及ＡＴＰ敏感钾电流的作用。方法：用膜片钳的全细胞记录方式观察钙电流和ＡＴＰ敏感钾电流。结果：酚妥拉明５，２５和１００μｍｏｌ·Ｌ＾－１对钙电流呈浓度依赖性和非电压依赖性的抑制作用，抑制率分别为１７％，２３％和３０％，而对电流－电压关系没有影响。这一抑制作用与酚妥拉明对α１和α２受体的作用无关。酚妥拉明１００μｍｏｌ·Ｌ＾－１可显著抑制ＤＮＰ诱导产生的ＡＴ     

N—甲基小檗胺对离体大鼠肝细胞外向钾电流的影响

AIM: To study the effects of N-methyl berbamine (NMB) on the delayed outward potassium currents (Ik) in isolated rat hepatocytes. METHODS: With patch-clamp techniques and whole-cell recording method, holding potential -50 mV, command potential +30 to +140 mV, duration 900 ms. RESULTS: NMB reduced Ik in a concentration-dependent manner. When the concentrations of NMB were 20, 50, 400 nmol.L-1 and 50 mumol.L-1, the amplitude values of Ik were decreased to 3.6 +/- 0.4 (P > 0.05), 2.1 +/- 1.6 (P > 0.05), 3.7 +/- 1.6 (P < 0.05), 2.3 +/- 1.3 nA (P < 0.01) from 4.4 +/- 1.0 (n = 4), 2.5 +/- 1.8 (n = 4), 5.8 +/- 2.1 (n = 5), 4.6 +/- 1.3 (n = 6) nA of control, respectively. The inhibitory rates were 10%, 15%, 37%, and 51%, respectively. CONCLUSION: NMB was a K+ channel inhibitor.     

大黄素对豚鼠单个心室肌细胞胞浆游离钙浓度及L-型钙电流的影响

目的研究大黄素(emodin)对豚鼠心室肌细胞钙信号的影响。方法酶解法分离豚鼠单个心室肌细胞,应用激光扫描共聚焦显微镜联合全细胞膜片钳技术测量豚鼠心室肌细胞钙信号的变化。结果在静息状态下,1～100 μmol·L^-1大黄素对［Ca²⁺］i均无影响;对60 mmol·L^-1 KCl诱导的外钙内流引起的胞浆钙升高有不同的影响,1 μmol·L^-1表现为促进作用;10 μmol·L^-1无作用;100 μmol·L^-1则表现为抑制作用。膜片钳研究结果表明,1 μmol·L^-1大黄素可明显促进L-型钙电流,10 μmol·L^-1对L-型钙电流无影响;100 μmol·L^-1明显抑制L-型钙电流。结论大黄素对心肌细胞内钙及L-型钙电流具有双向调节作用。     

Effects of berbamine on ATP-induced [Ca2+]i mobilization in cultured vascular smooth muscle cells and cardiomyocytes.

AIM: To study the effects of berbamine (Ber) on [Ca2+]i homeostasis induced by adenosine triphosphate (ATP) in vascular smooth muscle cells (VSMC) of rabbits and cardiomyocytes of rats. METHODS: Both cell types were cultured and loaded with Fura 3-AM. [Ca2+]i was measured by fluorescent intensity (FI) in each cell with confocal microscopy. RESULTS: (1) ATP 30 mumol.L-1 elevated [Ca2+]i in VSMC and cardiomyocytes, FI values reached 660 +/- 258 and 1058 +/- 252 from 250 +/- 84 and 218 +/- 76 at 19 s +/- 5 s and 11.8 s +/- 2.4 s, but FI in nucleus was not changed in VSMC. (2) Ber 30 mumol.L-1 did not affect the resting FI in both cell types, but prolonged the time to peak (P < 0.01) and reduced the FI elevated by ATP (P < 0.01), but not completely inhibited even at 100 mumol.L-1. (3) In D-Hanks' solution or in the presence of egtazic acid (EGTA) 3 mmol.L-1, the inhibitory effect of Ber was not seen (P > 0.05). (4) All effects of Ber on ATP-induced [Ca2+]i mobilization were similar to those of Ver 10 mumol.L-1. CONCLUSION: In VSMC and cardiomyocytes, ATP-induced CA2+ influx was inhibited by Ber and Ver, while the Ca2+ release was not.     

小檗胺对高钾,去甲肾上腺素及咖啡因引起大鼠心肌细胞内钙动拮？…

AIM: To study the effects of berbamine (Ber) on intracellular calcium concentration ([Ca2+]i) mobilized by KCl depolarization, norepinephrine (NE), and caffeine. METHODS: [Ca2+]i was measured with fluorescent intensity (FI) by confocal microscope in single cultured cardiomyocytes of newborn rats loaded with Fluo 3-AM 2 mumol.L-1. RESULTS: FI value of [Ca2+]i in control level was 248 +/- 70 in the presence of extracellular calcium 1.5 mmol.L-1 and was not changed by Ber 3-30 mumol.L-1. KCl (60 mmol.L-1)- and NE (30 mumol.L-1)-induced [Ca2+]i mobilizations were inhibited (P < 0.01) by Ber 30 mumol.L-1, similar to that of verapamil (Ver). The inhibitory effect of Ber on [Ca2+]i induced by KCl was further increased (P < 0.05) in the presence of egtazic acid 3 mmol.L-1, but that on [Ca2+]i induced by NE was not changed. The [Ca2+]i mobilized by caffeine 80 and 160 mumol.L-1 in D-Hanks' solution was not affected (P > 0.05) by Ber and Ver. CONCLUSION: Ber possessed the antagonistic effects on [Ca2+]i increases via voltage-dependent Ca2+ channel and receptor-operated Ca2+ channel in newborn rat cardiomyocytes, but without effect on intracellular Ca2+ release.     

Effects of berberine of L- and T-type calcium channels in guinea pig ventricular myocytes.

AIM: To study the effects of berberine (Ber) on L-(ICa,L) and T-type (ICa,T) channels in isolated guinea pig ventricular myocytes. METHODS: Using whole cell patch-clamp recording technique. RESULTS: Ber 10, 30 mumol.L-1 inhibited the ICa, L from 1400 +/- 247 pA to 978 +/- 204 pA (n = 5 cells of 5 guinea pigs, P < 0.05), and to 664 +/- 179 pA (n = 5, P < 0.01), respectively. The inhibitory effect was concentration-dependent and non-frequency-dependent. The peak value of ICa,L in the current-voltage relationship was decreased. Ber affected the inactivation kinetics of ICa,L. The half activation potential (V0.5) was shifted from -27.8 mV to -34.2 mV and the slope factor (kappa) was changed from 9.22 into 13.03. Ber did not affect the activation kinetics. Ber 10 and 30 mumol.L-1 also inhibited ICa,T (from 154 +/- 80 pA to 101 +/- 78 pA, and to 48 +/- 45 pA, n = 8 cells of 5 guinea pigs, P < 0.05). CONCLUSION: Ber possessed blocking effects on both L- and T-type calcium channels.     

小檗胺对培养的HeLa细胞内游离钙浓度的作用

AIM: To study the involvement of Ca2+ signaling and the effects of berbamine (Ber) on intracellular calcium concentration ([Ca2+]i) elevated in cultured HeLa cells. METHODS: [Ca2+]i was measured by confocal microscopy in single HeLa cell loaded with Fluo 3-AM. The change of [Ca2+]i was represented by fluorescent intensity (FI). RESULTS: (1) In the presence of extracellular Ca2+ 1.3 mmol.L-1, the resting level of FI was 186 +/- 44, n = 49 cells from all control experiments, and KCl, NE, caffeine, and calcimycin (Cal) all induced [Ca2+]i elevations in cultured HeLa cells. (2) The resting level of FI was not affected by pretreatment with Ber. The FI increased by KCl 60 mmol.L-1, NE 100 micromol.L-1, and Cal 30 micromol.L-1 were attenuated (P < 0.05 or P < 0.01), the slope and the time to peak of FI increase were decreased and prolonged. (3) In the absence of extracellular Ca2+, caffeine 80 mmol.L-1-induced [Ca2+]i mobilization was not inhibited by Ber 100 micromol.L-1 pretreatment. (4) These effects of Ber were similar to those of verapamil (Ver) 10 mumol.L-1. CONCLUSION: Although it was derived from cervical cancer, the HeLa cells which were belong to the nonexcitable cell possessed the similar biological properties with excitable cells, and Ca2+ also played a crucial role in signal transduction processes.     

MN-9202对兔血小板聚集、5-HT释放、TXB_2合成及Ca~(2 )转运的影响(英文)

目的:研究新二氢吡啶类钙拮抗剂MN-9202对兔血小板激活的影响,并探讨其作用机制。方法:以Fu-ra-2 AM为荧光探针,采用时间扫描方式记录血小板内Ca~(2 )的变化;分别用HPLC/ECD和放射免疫测定法检测5-HT及TXB_2。结果:MN-9202剂量依赖地抑制ADP或凝血酶诱导的血小板聚集,抑制TXA_2的释放并且能有效阻滞激活血小板胞内Ca~(2 )水平的增加。MN-9202 1μmol·L~(-1)能抑制胶原15mg·L~(-1)诱导的5-HT释放反应,但对胶原45mg·L~(-1)诱导的反应无抑制作用。结论:MN-9202阻滞血小板Ca~(2 )内流并抑制血小板花生四烯酸代谢及激活反应。     

蜂毒肽增强豚鼠心室肌细胞Na~ -Ca~(2 )交换电流(英文)

目的:研究蜂毒肽使心肌细胞钙超负荷的机制。方法:全细胞膜片箝记录。结果:蜂毒肽0.05,0.1μmol/L促进I_(Na)峰值(nA)从-2.1±0.8分别增加到-3.2±1.0(n=7,P<0.05)和-3.7±1.5(n=7,P<0.05)。蜂毒肽0.05,0.1,0.2μmol/L对I_(Ca)无显著性作用,但在箝制电位为 50mV时,促进I_(Na-Ca)(pA)从53±21分别增加到427±256(n=5,P<0.05),349±147(n=5,P<0.01)和320±97(n=5,P<0.05)。结论:蜂毒肽使心肌细胞内钙增加主要是由于促进Na~ -Ca~(2 )交换电流而不是L-型钙电流。