In the article by Kontaridis et al, “Deletion of Ptpn11 (Shp2) in Cardiomyocytes Causes Dilated Cardiomyopathy via Effects on the Extracellular Signal–Regulated Kinase/Mitogen-Activated Protein Kinase and RhoA Signaling Pathways” (Circulation. 2008;117:1423–1435), the information on the method of isolation of the cardiomyocytes (page 1424, last paragraph) was incorrect.
The beginning of that paragraph (until the sentence that begins, “After 12 hours”) should read:
Primary cardiomyocytes were isolated and cultured as previously described.30 Briefly, adult cardiomyocytes were obtained by heart Langendorff perfusion with Ca2+-free Tyrode buffer (135 mmol/L NaC1, 4 mmol/L KC1, 1 mmol/L MgC12, 0.33 mmol/L NaH2PO4, 10 mmol/L HEPES) and 10 mmol/L glucose (pH 7.4), 10 mmol/L 2,3-butanedione monoxime (Sigma, St Louis, Mo), and 5 mmol/L Taurine (Sigma) for 3 to 5 minutes. Perfusion was continued for 7 to 10 minutes with recirculating Tyrode solution containing collagenase D (0.3 mg/g body weight; Roche, Indianapolis, Ind), collagenase B (0.4 mg/g body weight; Roche), and proteinase XIV (0.05 mg/g body weight; Sigma). Ventricular tissue was then minced in Tyrode solution containing 2% bovine serum albumin (Sigma), incubated for 15 minutes at 37°C, and then filtered through a 250-μm nylon mesh. The cell suspension was centrifuged at 420g for 2 minutes and then gradually subjected to Tyrode solution with increasing concentrations of calcium and decreasing concentrations of 2,3-butanedione monoxime (final: 1.2 mmol/L CaC12, no 2,3-butanedione monoxime). Typical yields were 1.5 to 2.5×106 cells per heart with 70% to 80% of the cells retaining their rod-shaped morphology.
In addition, the original reference 30 should be replaced with the following reference:
Zhu M, Gach AA, Liu GX, Xu X, Lim CC, Zhang J, Mao L, Chuprun JK, Koch WJ, Liao R, Koren G, Blaxall BC, Mende U. Enhanced calcium cycling and contractile function in transgenic hearts expressing constitutively active G(alpha)o* protein. Am J Physiol Heart Circ Physiol. 2008;294:H1335–H1347.
These changes have been made to the online version of the article.
The authors regret these errors.