In vitro exposure of depolarized caudal artery preparations of the rat to a high calcium concentration resulted in a strong contraction of the smooth mus cle cells. This muscle contraction was suppressed by flunarizine. It was shown cytochemically, using the combined oxalate-pyroantimonate method for the lo calization of calcium, that a considerable amount of electron-dense precipitate was seen over the depolarized muscle cells after incubation in a calcium contain ing medium. On the other hand this precipitate was not present on the smooth muscle cells when flunarizine was added to this incubation medium. The reac tion product was only present in the extracellular space.
These results were controlled by Laser Microprobe Mass Analysis. By evap orating and ionizing small parts of the smooth muscle cells ( ± 1 μm), it was confirmed that the cytochemical method indeed demonstrated calcium, with negligible interference of other cations.
Get full access to this article
View all access options for this article.
References
1.
Borgers M., et al: Intranuclear microtubules in lung mast cells of guinea pigs in anaphylactic shock. Lab Invest37: 1, 1977.
2.
Borgers M., et al: Effects of flunarizine on the distribution of calcium in vascular smooth muscle. Blood Vessels17: 123, 1980.
3.
De Nollin S., et al: Influence of econazole and 5-fluorocytosine on the ultrastructure of Aspergillus fumigatus and the cytochemical localizaton of calcium, controlled by Laser Microprobe Mass Analysis. Sabouraudia21: 287, 1983.
4.
De Noyer E., et al: Laser Microprobe Mass Analysis. Anal Chem54: A26, 1982.
5.
Jacob W.A., et al: Subcellular Determination of Trace Amounts of CA++ ions in Biological Tissue. Journal of Trace and Microprobe Techniques.2:2; 161, 1985
6.
Diculescu I. , et al: Ultrastructural study of calcium distribution in cardiac muscle cells. Ztschr Zellforsch121: 181, 1971.
7.
Shaw F. and Morris J.: Calcium localization in the rat neuro-hypophysis. Nature287: 56, 1980.
