Abstract
The bioluminescent calcium indicator aequor in was successfully loaded into vascular smooth muscle cells ofAmphiuma tridactylum by either microinjection or a new method which makes the cells reversibly hyperpermeable. Both gave similar results; however, the latter method produced larger signals. Vasoconstrictors produced a sustained contraction and a light (calcium) response consisting of two component: a large transient followed by a smaller, sustained response. Electrical stimulation produced a light transient that was much briefer than the contraction. These results suggest that tension can be maintained in smooth muscle in the presence of lower calcium levels than those present during force development.
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References
Ashcroft FM, Stanfield PR (1981) Calcium dependence of the inactivation of the calcium currents in skeletal muscle fibers of an insect. Science 213:224–226
Blinks, JR (1982) The use of photoproteins as calcium indicators in cellular physiology. In: Techniques in the Life Sciences, Physiology Section, Vol. P1, Part II, Techniques in Cellular Physiology ed PF Baker) P126 pp 1–38. Elsevier Scientific Publishers Ltd, Shannon
Caffrey JM, Anderson NC (1978) Isolation of smooth muscle cells fromAmphiuma stomach. Fed Proc 37:639 (abstract)
El-Sharkawy TY, Morgan KG, Szurszewski JH (1978) Intracellular electrical activity of canine and human gastric smooth muscle. J Physiol 279:291–307
Fay FS, Shlevin HH, Granger WC, Taylor SR (1979) Aequorin luminescence during activation of single smooth muscle cells. Nature 280:506–508
Hagiwara, S, Naka KI (1964) The initiation of spike potential in barnacle muscle fibres under low intracellular Ca++. J Gen Physiol 48:141–162
Kostyuk PG, Krishtal OA (1977) Effects of calcium and calcium-chelating agents on the inward and outward currents in the membrane of mollusc neurons. J Physiol (London) 270:569–580
McClellan GB, Winegrad S (1978) The regulation of the calcium sensitivity of the contractile system in mammalian cardiac muscle. J Gen Physiol 72:737–764
Neering IR, Morgan KG (1980) Use of aequorin to study excitation-contraction coupling in mammalian smooth muscle. Nature 288:585–587
Prosser, CL, Burnstock G, Kahn J (1960) Conduction in smooth muscle: comparative structural properties. Am J. Physiol 199:545–552
Siegman MJ, Butler TM, Mooers SV, Davies RE (1976) Calcium-dependent resistance to stretch and stress relaxation in resting smooth muscles. Am J Physiol 231:1501–1508
Somlyo AP, Somlyo AV (1970) Vascular smooth muscle II. Pharmacology of normal and hypertensive vessels. Pharm Rev 22:249–353
Sutherland PJ, Stephenson DG, Wendt IR (1980) A novel method for introducing Ca++-sensitive photoproteins into cardiac cells. Proc Aust Phys Pharm Soc 11: 160 P (abstract)
Van Breemen C, Farinas BR, Casteels R, Gerba P, Wuytack F, Deth R (1973) Factors controlling cytoplasmic Ca2+ concentration. Phil Trans R Soc Lond B 57–71
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Morgan, J.P., Morgan, K.G. Vascular smooth muscle: The first recorded Ca2+ transients. Pflugers Arch. 395, 75–77 (1982). https://doi.org/10.1007/BF00584972
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DOI: https://doi.org/10.1007/BF00584972