title: Optimal temperature range for low-temperature preservation of dissociated neonatal rat cardiomyocytes.
abstract: The increase in demand for primary cardiomyocytes necessitates advanced methods for their stable supply. In this study, we investigated the optimal temperature range for preserving dissociated cardiomyocytes for 72 h while maintaining their normal growth and beating functions. Neonatal rat cardiomyocytes dissociated by collagenase and suspended in the culture medium were preserved at temperatures from -2 to 35°C for 72 h. The cardiomyocytes preserved at temperatures below 20°C maintained the initial dispersed states, whereas they aggregated robustly at higher temperatures. The viability of the dispersed cells after preservation was more than 80%. After the preservation, the microscopic observations during the 7-days cultivation indicated that these dispersed cardiomyocytes grew normally to form a confluent monolayer, and beat spontaneously and regularly during culture, as did the fresh cells. These systematic evaluations indicated that the optimal temperature ranged from 3 to 20°C. Below this optimal temperature range, the cell activities decreased slightly with temperature. The robustly aggregated cardiomyocytes exhibited weak growth and low beating rates, although some cardiomyocytes still survived. The optimal conditions, which consist of a wider temperature range and longer preservation period than the present commercially used conditions, allowed milder temperature control and thus more economical transportation for the dissociated primary cardiomyocytes.
authors: Division of Applied Physics, Faculty of Engineering, Hokkaido University, Kita-ku, Sapporo, Japan. t-uchida@eng.hokudai.ac.jp
authors: Tsutomu
authors: T
authors: Uchida
authors: Masafumi
authors: M
authors: Nagayama
authors: Toshio
authors: T
authors: Taira
authors: Kyoko
authors: K
authors: Shimizu
authors: Masato
authors: M
authors: Sakai
authors: Kazutoshi
authors: K
authors: Gohara
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002448:Cell Adhesion; D049109:Cell Proliferation; D002469:Cell Separation / Q000379:methods; D002470:Cell Survival / Q000502:physiology; D003080:Cold Temperature; D017364:Collagenases / Q000378:metabolism; D015925:Cryopreservation / Q000379:methods*; D003470:Culture Media; D008858:Microscopy, Phase-Contrast; D009200:Myocardial Contraction / Q000502:physiology*; D009206:Myocardium / Q000166:cytology*; D032383:Myocytes, Cardiac / Q000166:cytology / Q000502:physiology*; D061251:Primary Cell Culture; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D003470:Culture Media; D017364:Collagenases