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Histopathological alterations of the rat myocardium under simulated microgravity

미세중력 환경에 노출된 백서 심근 조직의 병리학적 변화

  • 김현수 (공군 항공우주의료원 항공우주의학연구센터) ;
  • 김윤화 (경희대학교 의과대학 병리학교실)
  • Received : 2012.08.03
  • Accepted : 2012.09.12
  • Published : 2012.09.30

Abstract

Spaceflight induces a number of cardiovascular physiological alterations. To study adaptations to microgravity on Earth, the tail-suspended, hindlimb-unloaded rat model has been used to simulate the effects of microgravity. Despite the extensive use of this model to infer physiological adaptations of many organs to microgravity, little information has been obtained on the effect of tail suspension(TS) on cardiac adaptations in the rat. This study was aimed to investigate the effects of simulated microgravity on the rat myocardium using the TS model. Twenty-four male Sprague-Dawley rats were randomly assigned to 3 experimental groups(1, 7 and 14 days of TS) and a control group. A microscopic examination was performed to assess histopathological changes in the myocardial morphology. The hearts from the control group, the 1 day-TS rats and the 7 day-TS rats revealed no evident abnormalities in cardiomyocyte size and morphology. At day 14 of TS, in contrast, the ventricular cardiomyocytes appeared more separated from each other and were slightly smaller in size compared with those of the control group. Also seen were scattered areas exhibiting focal disorganization of muscle fibers and some degenerating cardiomyocytes, of which the nuclei had become pyknotic or disappeared. In this study, we demonstrated that the ventricular cardiomyocytes underwent degeneration and atrophy at the microscopic level during exposure to simulated microgravity in TS rats.

References

  1. Morey-Holton, E. R., Globus, R. K., "Hindlimb unloading rodent model: technical aspects", Journal of Applied Physiology, Vol. 92, 2002, pp. 1367-1377. https://doi.org/10.1063/1.1492860
  2. Charles, J. B., Lathers, C. M., "Cardiovascular adaptation to spaceflight", Journal of Clinical Pharmacology, Vol. 31, 1991, pp. 1010-1023. https://doi.org/10.1002/j.1552-4604.1991.tb03665.x
  3. Levine, B. D., Zuckerman, J. H., Pawelczyk, J. A., "Cardiac atrophy after bed-rest deconditioning: a nonneural mechanism for orthostatic intolerance", Circulation, Vol. 96, 1997, pp. 517-525. https://doi.org/10.1161/01.CIR.96.2.517
  4. Perhonen, M. A., Franco, F., Lane, L. D., Buckey, J. C., Blomqvist, C. G., Zerwekh, J. E., "Cardiac atrophy after bed rest and spaceflight", Journal of Applied Physiology, Vol. 91, 2001, pp. 645-653. https://doi.org/10.1152/jappl.2001.91.2.645
  5. 이영복, 박종택, 임현교, 최재찬, 김순열, 조준 현, 이광호, "생쥐에서 하지무부하가 심혈관계 기능에 미치는 영향", 대한마취과학회지, 제53권, 2007, 222-228.
  6. Goldstein, M. A., Edwards, R. J., Schroeter, J. P., "Cardiac morphology after conditions of microgravity during COSMOS 2044", Journal of Applied Physiology, Vol. 73, 1992, pp. 94S-100S. https://doi.org/10.1152/jappl.1992.73.2.S94
  7. Ray, C. A., Vasques, M., Miller, T. A., Wilkerson, M. K., Delp, M. D., "Effect of short-term microgravity and long-term hindlimb unloading on rat cardiac mass and function", Journal of Applied Physiology, Vol. 91, 2001, pp. 1207-1213. https://doi.org/10.1152/jappl.2001.91.3.1207