Involvement of Cardiotrophin-1 in Cardiac Myocyte-Nonmyocyte Interactions During Hypertrophy of Rat Cardiac Myocytes In Vitro

Abstract

These results show that CT-1 secreted from cardiac nonmyocytes is significantly involved in the hypertrophic changes of cardiac myocytes in the coculture and suggest that CT-1 is an important local regulator in the process of cardiac hypertrophy.

Attenuation of Ischemic Myocardial Injury and Dysfunction by Cardiac Fibroblast-Derived Factor(s)

“…Interactions occur between cardiomyocytes and fibroblasts in the heart 4,22) . In this study, we demonstrated that the cardiac fibroblast -conditioned medium (CM) ameliorates the survival of cardiomyocytes in hypoxia.…”

“…), and the beating hearts were then excised. The aorta was quickly connected to the Langendorff's apparatus, suspended, and perfused with Krebs -Henseleit buffer (NaCl 118 mmol/L, KCl 4.7 mmol/L, MgSO 4 1.2 mmol/L, KH 2 PO 4 1.2 mmol/L, CaCl 2 1.8 mmol/L, NaHCO 3 25 mmol/L, glucose 11 mmol/L, pH 7.4), oxygenized with 95% O 2 and 5% CO 2 , and warmed at a constant temperature of 37°C 17) . The left atrium was opened and a latex balloon was inserted into the left ven-tricle (LV) to determine the left ventricular end -diastolic pressure (LVEDP).…”

“…Most non -cardiomyocytes are fibroblasts, which are known to possess a variety of activities such as the integration of myocardial tissue by producing extracellular matrix. Fibroblasts are also known to release several kinds of substances such as angiotensin II (AT II) 3) , cardiotrophin -1 (CT -1) 4) , endothelin -1 (ET -1) 5) , and leukemia -inhibitory factor (LIF) 6) . The main signal pathways downstream of AT II and ET -1 are phospholipase C (PLC) /phosphatidylinositol 3 -kinase (IP3) and diacylglycerol (DG) / protein kinase C (PKC) 7) .…”

Changes in the fluctuation of the contraction rhythm of spontaneously beating cardiac myocytes in cultures with and without cardiac fibroblasts

“…That is, we here investigated whether CF co-cultured with CM changed the development of the functional characteristics of cardiac myocytes. In fact, previous studies have revealed that non-myocytes secrete a humoral factor such as endothelin-1 (ET-1) or cardiotrophin-1 (CT-1) regulating the development of cardiac myocytes (Harada et al, 1997;Kuwahara et al, 1999). However, there is a possibility that MC-MC interactions are also critical to the development of MC themselves.…”

“…In fact, previous studies have revealed that non-myocytes secrete a humoral factor such as endothelin-1 (ET-1) or cardiotrophin-1 (CT-1) regulating the development of cardiac myocytes (Harada et al, 1997;Kuwahara et al, 1999).…”