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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:dateCreated |
1987-2-17
|
| pubmed:abstractText |
The hamster egg at fertilization shows transient, periodic hyperpolarizing responses due to a Ca2+-activated K+ conductance. The suggested increase of the intracellular Ca2+ concentration ([Ca2+]i) was measured with Ca2+-sensitive microelectrodes in combination with the voltage-clamp technique. Calculated values of the basal [Ca2+]i before fertilization averaged in the range 0.2-0.4 microM. Insemination of eggs induced periodic Ca2+ transients with exact one-to-one correspondence to periodic, Ca2+-activated K+ currents. They were recorded anywhere in the cytoplasm, even far from the site of sperm-egg fusion, indicating that [Ca2+]i increases in the whole egg upon each response. During a series of responses after insemination the increase in [Ca2+]i reached 1-2 microM in the first three responses and the peak value decreased to 0.7-0.8 microM in the later responses. The rise and decay times of each Ca2+ transient were 6.8 +/- 2.8 and 22 +/- 6 s (mean +/- S.D., n = 36), respectively. No significant difference in the amplitude and time course of the Ca2+ transient was detected in relation to the depth of the cytoplasm about 3-30 micron from the surface. The basal [Ca2+]i increased gradually from 0.39 to 0.56 microM (average in fourteen eggs) during the series of Ca2+ transients. The biological significance and mechanism of the periodic increase in [Ca2+]i and the response time of the Ca2+ electrode are discussed.
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| pubmed:commentsCorrections |
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-10605450,
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-27335,
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-326602,
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-352627,
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-383006,
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-3838803,
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-6136975,
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-6278501,
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-6411906,
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-6490715,
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-6887062,
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-6894326,
http://linkedlifedata.com/resource/pubmed/commentcorrection/2432241-7412868
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| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Aug
|
| pubmed:issn |
0022-3751
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
377
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
193-205
|
| pubmed:dateRevised |
2009-11-18
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| pubmed:meshHeading |
pubmed-meshheading:2432241-Action Potentials,
pubmed-meshheading:2432241-Animals,
pubmed-meshheading:2432241-Calcium,
pubmed-meshheading:2432241-Cricetinae,
pubmed-meshheading:2432241-Cytoplasm,
pubmed-meshheading:2432241-Ion Channels,
pubmed-meshheading:2432241-Ovum,
pubmed-meshheading:2432241-Potassium,
pubmed-meshheading:2432241-Time Factors,
pubmed-meshheading:2432241-Zygote
|
| pubmed:year |
1986
|
| pubmed:articleTitle |
Periodic increase of cytoplasmic free calcium in fertilized hamster eggs measured with calcium-sensitive electrodes.
|
| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|