ID | 32442 |
JaLCDOI | |
フルテキストURL | |
著者 |
Saito, Daiji
Okayama University
Yasuhara, Koichiro
Okayama University
Takeda, Kou
Okayama University
Hyodo, Tatsuo
Okayama University
Fujii, Akinobu
Okayama University
Uchida, Toshiaki
Okayama University
Abe, Yukihiro
Okayama University
Haraoka, Shoichi
Okayama University
Nagashima, Hideo
Okayama University
|
抄録 | The effects of intravenous infusion of isoproterenol on stenosis resistance were studied in the anesthetized open-chest dog. The circumflex coronary artery (LCx) was isolated near its origin and an electromagnetic flow transducer was placed around the vessel for measuring coronary flow. A polyethylene catheter was inserted into the small branch of LCx for monitoring distal coronary pressure. LCx was constricted with a thick cotton string to a degree of obstruction that eliminated reactive hyperemia following a 20-second coronary occlusion. The coronary resistance across the stenotic segment (RL) was calculated as the pressure gradient across the stenosis divided by coronary flow. Isoproterenol was infused intravenously in a dose to keep the heart rate at a level 25-30% above the control with and without coronary constriction. For maintaining the ascending aortic pressure at the pre-isoproterenol level, the descending thoracic aorta was constricted with a tape. In the absence of coronary constriction, the vascular resistance of large coronary arteries was not affected by isoproterenol with a significant increase in coronary flow. In the presence of coronary stenosis, isoproterenol markedly increased RI regardless of additional aortic constriction. The magnitude of the increase in RL during aortic constriction varied directly with the percent increase in the pressure gradient across the coronary stenosis. Pacing-tachycardia essentially did not affect RL. These results suggest that isoproterenol increased the vascular resistance of the stenotic segment with fixed caliber. |
キーワード | coronary cinstriction
open-chest dog
distal coronary pressure
|
Amo Type | Article
|
出版物タイトル |
Acta Medica Okayama
|
発行日 | 1983-02
|
巻 | 37巻
|
号 | 1号
|
出版者 | Okayama University Medical School
|
開始ページ | 59
|
終了ページ | 66
|
ISSN | 0386-300X
|
NCID | AA00508441
|
資料タイプ |
学術雑誌論文
|
言語 |
英語
|
論文のバージョン | publisher
|
査読 |
有り
|
PubMed ID | |
Web of Science KeyUT |