2024-03-29T10:54:53Z
https://nagoya.repo.nii.ac.jp/oai
oai:nagoya.repo.nii.ac.jp:00001387
2023-01-26T06:06:21Z
329:333:334:335
Role of Ca^<2+> Release from Sarcoplasmic Reticulum in Pacemaker Activity of the Sinoatrial Node
HONJO, Haruo
3194
INADA, Shin
3195
NIWA, Ryoko
3196
SHIBATA, Nitaro
3197
MITSUI, Kazuyuki
3198
BOYETT, Mark R.
3199
KAMIYA, Kaichiro
3200
KODAMA, Itsuo
3201
sinoatrial node
pacemaker activity
ryanodine
sarcoplasmic reticulum
extracellular potential mapping
2002-12
Recent studies using confocal microscopy combined with patch clamping on single sinoatrial (SA) node pacemaker cells suggest that Ca^<2+> release from the sarcoplasmic reticulum (SR) during diastole may play a prominent role in the late phase of pacemaker depolarization. The present study was designed to test this hypothesis in the intact SA node. We investigated the effects of a high concentration of ryanodine, which is known to disable SR Ca^<2+> release, on spontaneous activity of isolated rabbit right atrium including the whole SA node by using an extracellular potential mapping technique. Inhibition of SR Ca^<2+> release by 30 μM ryanodine caused only a moderate reduction of the spontaneous firing rate (by 20.0±2.8 %, n=4) of the intact SA node. This observation is inconsistent with previous data obtained from single pacemaker cells. Physiological significance of SR Ca^<2+> release in the regulation of SA node pacemaker activity is still unsettled.
国立情報学研究所で電子化したコンテンツを使用している。
departmental bulletin paper
Research Institute of Environmental Medicine, Nagoya University
2002-12
Environmental medicine : annual report of the Research Institute of Environmental Medicine, Nagoya University
1/2
46
98
100
http://hdl.handle.net/2237/2797
02870517
eng