Effects of defolliculation on membrane current responses of Xenopus oocytes.
Effects of defolliculation on membrane current responses of Xenopus oocytes.
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去卵泡对非洲爪蟾卵母细胞膜电流反应的影响。
DOI：
10.1113/jphysiol.1989.sp017780
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Woodward,RM
中科院分区：
文献类型：
--
作者：
Miledi,R;Woodward,RM
1.儿茶酚胺、腺苷、促性腺激素、血管活性肠肽（VIP）和E系列前列腺素都能在卵泡封闭的爪蟾卵母细胞中引起K+电流。有证据表明，环核苷酸作为细胞内的信使在激活这种K+电导。毒蕈碱激动剂和一些二价阳离子（如Co2+、Mn 2+、Ni 2+和Cd 2+）引起缓慢振荡的Cl-电流，通过肌醇磷脂水解和肌醇磷酸盐动员细胞内钙激活。2.我们研究了这些膜电流反应是否产生于卵母细胞本身或在被包裹的滤泡细胞，其通过间隙连接与卵母细胞偶联。使用胶原酶酶促或通过手动解剖结合在聚-L-赖氨酸包被的载玻片上滚动，对卵母细胞进行去卵泡。使用扫描电子显微镜检查滤泡细胞的去除。将去卵泡卵母细胞的膜电流反应与取自同一卵巢的卵泡封闭卵母细胞中观察到的反应进行比较。3.由所有各种激素/神经递质引起的K+反应要么急剧减少（大于90%），要么通过去卵泡化消除。在去卵泡卵母细胞中，腺苷酸环化酶激活剂forskolin和卵母细胞内注射环磷酸腺苷（cAMP）或环磷酸鸟苷产生的K+电流同样减少。相反，通过去卵泡选择性地保留了乙酰胆碱和二价阳离子的振荡Cl-电流。4.将环AMP（1 - 20 pmol）注射到去卵泡卵母细胞中对ACh引起的振荡Cl-电流几乎没有影响。然而，通过卵母细胞膜去极化激活的钙依赖性瞬时Cl-电流通过注射环AMP（1 - 10 pmol）持续增强（100 - 900%）。5.这些实验表明，环核苷酸激活的K+电流主要出现在卵泡细胞中，并通过间隙连接的电耦合在卵母细胞内进行监测。由ACh和二价阳离子引起的振荡性Cl-反应大部分或全部在卵母细胞本身产生。
1. Catecholamines, adenosine, gonadotrophins, vasoactive intestinal peptide (VIP) and E‐series prostaglandins all elicit K+ currents in follicle‐enclosed Xenopus oocytes. Evidence suggests that cyclic nucleotides act as intracellular messengers in the activation of this K+ conductance. Muscarinic agonists and some divalent cations (e.g. Co2+, Mn2+, Ni2+ and Cd2+) elicit slow oscillatory Cl‐ currents, which are activated through hydrolysis of inositol phospholipids and mobilization of intracellular calcium by inositol phosphates. 2. We investigated whether these membrane current responses were generated in the oocyte itself or in enveloping follicular cells which are coupled to the oocyte by gap junctions. Oocytes were defolliculated, either enzymatically using collagenase, or by manual dissection combined with rolling over poly‐L‐lysine‐coated slides. Removal of follicular cells was checked using scanning electron microscopy. Membrane current responses of defolliculated oocytes were compared with responses seen in follicle‐enclosed oocytes taken from the same ovary. 3. The K+ responses evoked by all the various hormones/neurotransmitters were either drastically reduced (greater than 90%) or abolished by defolliculation. K+ currents generated by the adenylate cyclase activator forskolin and by intraoocyte injection of adenosine 3',5'‐cyclic monophosphate (cyclic AMP), or guanosine 3',5'‐cyclic monophosphate were similarly reduced in defolliculated oocytes. In contrast, oscillatory Cl‐ currents to acetylcholine and divalent cations were selectively preserved through defolliculation. 4. Injection of cyclic AMP (1‐20 pmol) into defolliculated oocytes had little or no effect on oscillatory Cl‐ currents elicited by ACh. However, the calcium‐dependent transient Cl‐ current, activated by depolarization of the oocyte membrane, was consistently potentiated (100‐900%) by injections of cyclic AMP (1‐10 pmol). 5. These experiments suggest that cyclic nucleotide‐activated K+ currents arise essentially in follicular cells and are monitored within the oocyte through electrical coupling by gap junctions. Oscillatory Cl‐ responses evoked by ACh and divalent cations are produced largely or wholly in the oocyte itself.
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影响因子：
56.9
作者：
KOBILKA, BK;KOBILKA, TS;LEFKOWITZ, RJ
通讯作者：
LEFKOWITZ, RJ
爪蟾卵母细胞中外源信使 RNA 诱导的血清素受体
DOI：
10.1098/rspb.1983.0062
发表时间：
1983
期刊：
Proceedings of the Royal Society of London. Series B. Biological Sciences
影响因子：
--
作者：
C. Gundersen;R. Miledi;I. Parker
通讯作者：
I. Parker
DOI：
10.1073/pnas.79.10.3188
发表时间：
1982-01-01
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES
影响因子：
--
作者：
BAUD, C;KADO, RT;MARCHER, K
通讯作者：
MARCHER, K
影响因子：
64.8
作者：
LOTAN, I;DASCAL, N;LASS, Y
通讯作者：
LASS, Y
乙酰胆碱和佛波酯抑制爪蟾卵母细胞中腺苷和 cAMP 引起的钾电流。
DOI：
10.1073/pnas.82.17.6001
发表时间：
1985
影响因子：
11.1
作者：
Dascal,N;Lotan,I;Gillo,B;Lester,HA;Lass,Y
通讯作者：
Lass,Y