Original ArticleLong-Term Effects of Growth Hormone on Infarct Size and Left Ventricular Function in Sheep With Coronary Artery OcclusionOlea, Fernanda D PhD*; De Lorenzi, Andrea MD†; Cortés, Claudia MD‡; Cabeza Meckert, Patricia MSc§; Cendoya, Oscar MD‡; Barra, Juan G DVM, PhD*; Bercovich, Andrés PhD¶; González, Eliseo MSc¶; Laguens, Rubén MD, PhD§; Crottogini, Alberto MD, PhD*Author Information From the *Department of Physiology, Favaloro University, Buenos Aires, Argentina; †Departments of Echocardiography; and ‡Nuclear Medicine, Favaloro University Hospital, Buenos Aires, Argentina; §Department of Pathology, Favaloro University, Buenos Aires, Argentina; and ¶Bio Sidus S.A., Buenos Aires, Argentina. Received for publication July 31, 2009; accepted December 10, 2009. Supported by grant # PID 268 from the National Agency for Scientific and Technological Promotion of Argentina, Ministry for Science, Technology and Innovative Production. A. Crottogini is an established investigator of the National Council for Scientific and Technical Investigations of Argentina. Recombinant human growth hormone was kindly provided by Bio Sidus S.A., Buenos Aires, Argentina. Disclosures: A. Bercovich and E. González are scientist of Bio Sidus S.A., the company producing the human recombinant growth hormone used in the present study. The authors report no conflicts of interest. Reprints: Alberto J. Crottogini, MD, PhD, Department of Physiology, Favaloro University, Solís 453 (1078) Buenos Aires, Argentina (e-mail: [email protected]). Journal of Cardiovascular Pharmacology: March 2010 - Volume 55 - Issue 3 - p 255-261 doi: 10.1097/FJC.0b013e3181cf9190 Buy Metrics Abstract The effects of growth hormone (GH) on infarct size and left ventricular (LV) function in experimental acute myocardial infarction (AMI) have been controversial. Moreover, little, if any, information exists regarding long-term evaluation of therapeutic doses of GH in large mammalian models of AMI. We therefore aimed to assess the effect of therapeutic doses of GH over 3.5 months on infarct size and heart function in sheep with AMI. After coronary artery ligation, sheep received subcutaneous human GH 8 IU/d (n = 8) or vehicle (n = 8) over 100 days. Infarct area was similar in GH (16.9% ± 3% of LV area) and placebo (16.5% ± 3.7%, P = not significant) sheep. At 3 days of treatment onset, but not at later times, GH sheep had higher LV shortening fraction (30.7% ± 3.5% vs. 24.8% ± 6.1%, P < 0.04), systolic anterior wall thickness (10.1 ± 0.8 vs. 8.6 ± 1.2 mm, P < 0.02), and cardiac index (3.8 ± 0.6 vs. 2.8 ± 0.7 L·min−1·m−2, P < 0.01). This evolution of function parameters paralleled that of serum insulin-like growth factor 1 levels, which differed significantly only during the first week, suggesting a direct effect of GH on LV contractility. These results may suggest the usefulness of therapeutic doses of GH at the early phases of AMI but do not support maintaining the treatment for longer time. © 2010 Lippincott Williams & Wilkins, Inc.