Summary
The ultrastructure of the vascular smooth muscle cells of the middle cerebral artery in 6-month-old male stroke-prone spontaneously hypertensive rats (SHRSP) was studied by scanning (SEM) and transmission electron microscopy (TEM) and compared with that of age-matched normotensive Wistar Kyoto rats (WKY). Although the smooth muscle cells of WKY rats by SEM had a typical spindle shape and smooth surface texture, those of SHRSP were structurally modified by numerous surface invaginations and projections, bearing some structural resemblance to the myotendinous junction of skeletal muscle. Structural modifications affected more than half the surface of medial smooth muscle cells in SHRSP, but less than 0.6% of the surface of these cells in WKY rats. About 10% of medial smooth muscle cells were necrotic in SHRSP, but no necrotic cells were identified in WKY rats. By TEM, smooth muscle cells in SHRSP were shown to be irregular in profile with deep indentations of the plasma membrane and were surrounded by many layers of basal laminalike material. The present study suggests that most smooth muscle cells in the middle cerebral artery of SHRSP may be modified to adapt to chronic hypertension by increasing the junctional area between muscle cells and connective tissue and that some cells may undergo necrosis.
Similar content being viewed by others
References
Brayden JE, Halpern W, Brann LR (1983) Biochemical and mechanical properties of resistance arteries from normotensive and hypertensive rats. Hypertension 5:17–25
Chaldakov GN, Nara Y, Horie R, Yamori Y (1989) A new view of the arterial smooth muscle cells and autonomic nerve plexus by scanning electron microscopy in spontaneously hypertensive rats. Exp Pathol 36:181–184
Folkow B, Hallbäck M, Lundgren Y, Sivertsson R, Weiss L (1973) Importance of adaptive changes in vascular design for establishment of primary hypertension, studied in man and in spontaneously hypertensive rats. Circ Res [Suppl 1] 32-33:2–16
Fujiwara T, Uehara Y (1982) Scanning electron microscopical study of vascular smooth muscle cells in the mesenteric vessels of the monkey: Arterial smooth muscle cells. Biomed Res 3:649–658
Gabella G (1983) An introduction to the structural variety of smooth muscles. In: Bevan JA, Maxwell RA, Shibata S, Fujiwara M, Mohri K, Toda N (eds) Vascular neuroeffector mechanisms. 4th International Symposium. Raven Press, New York, pp 13–35
Greenwald SE, Berry CL (1978) Static mechanical properties and chemical composition of the aorta of spontaneously hypertensive rats: a comparison with the effects of induced hypertension. Cardiovasc Res 12:364–372
Harper SL, Bohlen HG (1984) Microvascular adaptation in the cerebral cortex of adult spontaneously hypertensive rats. Hypertension 6:408–419
Hart MN, Heistad DD, Brody MJ (1980) Effect of chronic hypertension and sympathetic denervation on wall/lumen ratio of cerebral vessels. Hypertension 2:419–423
Heistad DD, Marcus ML, Abboud FM (1978) Role of large arteries in regulation of cerebral blood flow in dogs. J Clin Invest 62:761–768
Hertel R, Henrich H, Assmann R (1977) Intravital measurement of arteriolar pressure and tangential wall stress in normotensive and spontaneously hypertensive rats (established hypertension). Experientia 34:865–867
Ishikawa H, Sawada H, Yamada E (1983) Surface and internal morphology of skeletal muscle. In: Peachey Ld, Adrian Rh, Geiger Sr (eds) Handbook of physiology, Sect 10, skeletal muscle. Am Physiol Soc, Bethesda Maryland, pp 1–21
Kontos HA, Wei EP, Navari RM, Levasseur JE, Rosenblum WI, Patterson JL Jr (1978) Responses of cerebral arteries and arterioles to acute hypotension and hypertension. Am J Physiol 234:H371-H383
Korsgaard N, Mulvany MJ (1988) Cellular hypertrophy in mesenteric resistance vessels from renal hypertensive rats. Hypertension 12:162–167
Lee RMKW (1985) Vascular changes at the prehypertensive phase in the mesenteric arteries from spontaneously hypertensive rats. Blood Vessels 22:105–126
Lee RMKW, Forrest JB, Garfield RE, Daniel EE (1983) Ultrastructural changes in mesenteric arteries from spontaneously hypertensive rats. A morphometric study. Blood Vessels 20:72–91
Miller BG, Connors BA, Bohlen HG, Evan AP (1987) Cell and wall morphology of intestinal arterioles from 4-to 6- and 17-to 19-week-old Wistar-Kyoto and spontaneously hypertensive rats. Hypertension 9:59–68
Mulvany MJ (1983) Do resistance vessel abnormalities contribute to the elevated blood pressure of spontaneously-hypertensive rats? A review of some of the evidence. Blood Vessels 20:1–22
Mulvany MJ, Baandrup U, Gundersen HJG (1985) Evidence for hyperplasia in mesenteric resistance vessels of spontaneously hypertensive rats using a three-dimensional disector. Circ Res 57:794–800
Nordborg C, Fredriksson K, Johansson BB (1985) The morphometry of consecutive segments in cerebral arteries of normotensive and spontaneously hypertensive rats. Stroke 16:313–320
Nordborg C, Ivarsson H, Johansson BB, Stage L (1983) Morphometric study of mesenteric and renal arteries in spontaneously hypertensive rats. J Hypertension 1:333–338
Nordborg C, Johansson BB (1980) Morphometric study on cerebral vessels in spontaneously hypertensive rats. Stroke 11:266–270
Okamoto K, Aoki K (1963) Development of a strain of spontaneously hypertensive rats. Jpn Circ J 27:282–293
Okamoto K, Yamori Y, Nagaoka A (1974) Establishment of the stroke-prone spontaneously hypertensive rat (SHR). Circ Res 34-35 (Suppl 1): 143–153
Ooshima A, Fuller G, Cardinale G, Spector S, Udenfriend S (1975) Collagen biosynthesis in blood vessels of brain and other tissues of the hypertensive rat. Science 190:898–900
Sadoshima S, Busija DW, Heistad DD (1983) Mechanisms of protection against stroke in stroke-prone spontaneously hypertensive rats. Am J Physiol: H406-H412
Spiro D, Lattes RG, Wiener J (1965) The cellular pathology of experimental hypertension. Am J Pathol 47:19–49
Tagami M, Nara Y, Kubota A, Sunaga T, Maezawa H, Fujino H, Yamori Y (1987) Ultrastructural characteristics of occluded perforating arteries in stroke-prone spontaneously hypertensive rats. Stroke 18:733–740
Takebayashi S (1985) Ultrastructural morphometry of hypertensive medial damage in lenticulostriate and other arteries. Stroke 16:449–453
Takebayashi S, Kaneko M (1983) Electron microscopic studies of ruptured arteries in hypertensive intracerebral hemorrhage. Stroke 14:28–36
Tidball JG (1984) Myotendinous junction: Morphological changes and mechanical failure associated with muscle cell atrophy. Exp Molec Pathol 40:1–12
Tidball JG, Daniel TL (1986) Myotendinous junctions of tonic muscle cells: structure and loading. Cell Tissue Res 245:315–322
Todd ME, Friedman SM (1972) The ultrastructure of peripheral arteries during the development of DOCA hypertension in the rat. Z Zellforsch 128:538–554
Trotter JA, Samora A, Baca J (1985) Three-dimensional structure of the murine muscle-tendon junction. Anat Rec 213:16–25
Uehara Y, Fujiwara T (1984) The morphological changes of arterial smooth muscle cells upon vasodilation and vasoconstriction. In: Courtice FC, Garlick DG, Perry MA (eds) Progress in microcirculation research II. The University of New South Wales, Sidney, pp 405–410
Werber AH, Heistad DD (1984) Effects of chronic hypertension and sympathetic nerves on the cerebral microvasculature of stroke-prone spontaneously hypertensive rats. Circ Res 55:286–294
Winquist RJ, Bohr DF (1983) Structural and functional changes in cerebral arteries from spontaneously hypertensive rats. Hypertension 5:292–297
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Fujiwara, T., Kondo, M. & Tabei, R. Morphological changes in cerebral vascular smooth muscle cells in stroke-prone spontaneously hypertensive rats (SHRSP). Virchows Archiv B Cell Pathol 58, 377–382 (1989). https://doi.org/10.1007/BF02890095
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02890095