@article{oai:dmu.repo.nii.ac.jp:00000421, author = {Nakajima, Takahide and Matsuda, Ryuko and Shinozaki, Makoto and Abe, Shichiro and Suzuki, Hidehiko}, issue = {1}, journal = {Dokkyo journal of medical sciences}, month = {Mar}, note = {Heart failure patients have been shown to have an increased blood norepinephrine concentration, and patients with a high norepinephrine concentration have a poor prognosis. Norepinephrine is a catecholamine with α_1 and β_1 effects, which lead to a vasoconstrictive action and enhancement of myocardial contraction. However, the consequences of norepinephrine-induced changes in myocardial blood flow in heart failure patients remain unknown. In this study, the influence of norepinephrine on hemodynamics and blood flow in the left ventricular myocardium was investigated using rats with and without a calcium load. Norepineph-rine without a calcium load induced a 29.3% reduction of myocardial blood flow (MBF), but had no significant effect on ejection fraction (EF) and left ventricular end-diastolic pressure (LVEDP). With simultaneous calcium administration, norepinephrine induced a 33.2% reduction of MBF and increased LVEDP significantly, but caused no reduction in EF. These results suggest that norepinephrine decreases MBF but has no effects on systolic function, and increases LVEDP and decreases MBF more markedly in combination with calcium., 原著, Original}, pages = {35--41}, title = {Effects of Norepinephrine on Left Ventricular Hemodynamics and Myocardial Blood Flow in Rats with and without Calcium Overload}, volume = {33}, year = {2006} }