Direct, Autocrine and Paracrine Effects of Cyclic Stretch on Growth of Myocytes and Fibroblasts Isolated from Neonatal Rat Ventricles

• Published in: Archives of physiology and biochemistry Vol. 109; no. 1; pp. 10 - 18
• Main Authors: Ruwhof, C., van Wamel, A.E.T., van der Valk, L.J.M., Schrier, P.I., van der Laarse, A.
• Format: Journal Article
• Language: English
• Published: Basingstoke Informa UK Ltd 2001; Taylor & Francis
• Subjects: Animals; Animals, Newborn; Atrial Natriuretic Factor - biosynthesis; Autocrine Communication - physiology; Biological and medical sciences; Cardiology. Vascular system; Cell Division; Cells, Cultured; DNA - metabolism; Fibroblasts - cytology; Heart; Heart failure, cardiogenic pulmonary edema, cardiac enlargement; Hyperplasia; Hypertrophy; Medical sciences; Muscle Contraction; Myocardium - cytology; Paracrine Communication - physiology; Rats; Rats, Wistar; Time Factors; Heart; Cell proliferation; Rat; Pathogenesis; Rodentia; Cardiovascular disease; Smooth muscle; DNA synthesis; Heart ventricle; Biomechanics; Autocrine secretion; Vertebrata; Mammalia; Mechanical stress; Cyclic; Protein synthesis; Heart disease; Newborn animal; Paracrine secretion; Circulatory system; Fibroblast; Stretching; Hypertrophy
• ISSN: 1381-3455; 1744-4160
• DOI: 10.1076/apab.109.1.10.4285

Several studies have demonstrated that static stretch of cardiomyocytes induces cardiomyocyte hypertrophy. We investigated the effects of cyclic stretch, a more physiological stimulus, on protein synthesis and DNA synthesis of rat ventricular cardiomyocytes and cardiofibroblasts. Further-more, we investigated whether these effects are caused by autocrine mechanisms. In addition, we studied the paracrine influences of stretched cardiofibroblasts on cardiomyocyte growth. Short-term cyclic stretch (0-24 h) of cardiomyocytes induced a growth response indicative of cardiomyocyte hypertrophy, given the fact that increased rates of protein synthesis and DNA synthesis were accompanied by an ele-vated release of atrial natriuretic peptide into the culture medium. In cardiofibroblasts, short-term cyclic stretch also induced a growth response as indicated by an increased rate of protein synthesis and DNA synthesis. Furthermore, incubation of stationary cardiofibroblasts with conditioned medium derived from stretched cardiofibroblasts revealed an autocrine effect of stretch as illustrated by an increased rate of protein synthesis in stationary cardiofibroblasts. In analogy, there was an autocrine effect of stretch on stationary cardiomyocytes incubated with con-ditioned medium derived from stretched cardiomyocytes. Moreover, we observed a paracrine effect of the conditioned medium derived from stretched cardiofibroblasts on station-ary cardiomyocytes. Thus, short-term cyclic stretch of cardiomyocytes and cardiofibroblasts induces growth responses that are the result of direct, autocrine, and paracrine effects. These autocrine/paracrine effects of stretch are most probably due to release of factors from stretched cells.