Advertisement

Heart and Vessels

, Volume 4, Issue 2, pp 94–99 | Cite as

Enhanced growth rate of cultured smooth muscle cells from spontaneously hypertensive rats

  • Yukio Yamori
  • Takehiro Igawa
  • Toshimi Kanbe
  • Yasuo Nara
  • Motoki Tagami
Originals

Summary

Smooth muscle cells were isolated and cultured from the aortic media of age-matched, stroke-prone and stroke-resistant spontaneously hypertensive rats (SHRSP, SHRSR: SHRs) and Wistar-Kyoto rats (WKY), and the growth rate of cells from the three strains was compared. Under electron microscopical observation the cells were identified as modified (or synthetic-type) smooth muscle cells. Cells occurring at low densities showed the same morphology for both SHRs and WKY, but cells occurring at higher densities were observed to be smaller in SHRs than in WKY. An analysis of the growth curves of cells showed a significantly enhanced replication rate in cells from SHRs compared with those from WKY, especially in the early passages. In later passages (repeated until the 9th passage), however, this distinction was not clear. These growth characteristics were also confirmed in cells from both 12- and 24-week-old, age-matched SHRs and WKY. We could not find any difference between the growth characteristics of cells from SHRSP and SHRSR. It is possible to hypothesize from these findings that the abnormality relating to hypertension (hypertension being a common characteristic of SHRSR and SHRSP) is found in the smooth muscle cells, and is reflected as an enhanced growth rate when they are exposed to mitogenic stimuli, such as in atherosclerosis.

Key words

Hypertension Spontaneously hypertensive rats Cultured smooth muscle cells Growth rate 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Sternby NH (1977) Atherosclerosis and risk factors. In: Schettler et al. (eds) Atherosclerosis IV. Springer, Berlin Heidelberg New York, pp 102–104Google Scholar
  2. 2.
    Hypertension Detection and Follow-up Program Cooperative Group (1979) Five-year findings of the hypertension detection and follow-up program. I. Reduction in mortality of persons with high blood pressure, including mild hypertension. JAMA 242: 2562Google Scholar
  3. 3.
    Ross R (1986) The pathogenesis of atherosclerosis—an update. N Engl J Med 314: 488–500PubMedGoogle Scholar
  4. 4.
    Yamori Y (1983) Physiopathology of the various strains of spontaneously hypertensive rats. In: Gegest J et al. (eds) Hypertension—physiopathology and treatment, 2nd edn. McGraw-Hill, New York, p 556Google Scholar
  5. 5.
    Tanase H, Suzuki Y, Ooshima A, Yamori Y, Okamoto K (1970) Genetic analysis of blood pressure in spontaneously hypertensive rats. Jpn Circ J 34: 1197–1212PubMedGoogle Scholar
  6. 6.
    Ross R (1971) The smooth muscle cell. Growth of smooth muscle in culture and formation of elastic fibers. J Cell Biol 50: 172–186PubMedGoogle Scholar
  7. 7.
    Lewis LJ (1979) Plasminogen activator from cultured cells. Thromb Haemost 42: 895–900PubMedGoogle Scholar
  8. 8.
    Simpson FO, Waal-Manning HJ, Bolli P (1978) Relationship of blood pressure to sodium excretion in a population survey. Clin Sci Mol Med 55: 373Google Scholar
  9. 9.
    Igawa T, Nara Y, Kihara M, Horie R, Yamori Y (1983) Cellular mechanisms of salt sensitivity in hypertension. NZ Med J 96: 859–860Google Scholar
  10. 10.
    Chamley-Campbell J, Campbell GR (1981) What controls smooth muscle phenotype? Atherosclerosis 40: 347–357PubMedGoogle Scholar

Copyright information

© Springer-Verlag 1988

Authors and Affiliations

  • Yukio Yamori
    • 1
  • Takehiro Igawa
    • 1
  • Toshimi Kanbe
    • 1
  • Yasuo Nara
    • 1
  • Motoki Tagami
    • 2
  1. 1.Department of PathologyShimane Medical UniversityIzumoJapan
  2. 2.Department of Internal MedicineSanraku HospitalTokyoJapan

Personalised recommendations