The development of a tissue calcium-detecting apparatus
Saito, M.; Aoki, K.; Takeuchi, K.; Hasegawa, M.; Arai, K.; Sato, T.
Rinsho Byori. Japanese Journal of Clinical Pathology 43(2): 169-176
1995
ISSN/ISBN: 0047-1860 PMID: 7699932 Document Number: 445171
Calcium phosphate is deposited in tissues with progression of aging and arteriosclerosis, causing impairments of organ functions. Localization and quantification of tissue calcium phosphate are important for elucidation of the cause of this calcium phosphate deposition. Tissue calcium phosphate has been detected by Von Kossa-Nishiyama staining using the heavy metal substitution technique. By this method, however, the reaction was weak because of the use of sunbeam as the light source, and consistent detection was difficult. Especially, fine calcium phosphate granules that appear in early stages of the pathological changes could not be detected. Therefore, we evaluated a method for preparation of tissue specimens, light source, filter, and staining conditions, and developed a more reliable method for detection and assay of tissue calcium phosphate. The human aortic tissue was fixed with formalin, embedded with paraffin, and cut to a thickness of 4 microns using a glass knife. Solax-XCA100B, an artificial sunbeam lamp with a spectrum nearly identical with that of the sun, was used as the light source. A B filter, which selectively filters out the wavelengths 290nm or less and 800-1,000nm, was used. The appearance of abnormal granules due to excessive reaction could be prevented by eliminating ultraviolet rays with wavelengths of 290nm or less, and burning of the tissue and the appearance of silver particles could be prevented by excluding infrared rays with wavelengths of 800nm or above. Distilled water was continuously dripped into the reaction solution to prevent an increase in the concentration due to evaporation. The reaction showed appreciable progression until after 40 minutes and stopped completely after 80 minutes.