Kazue Yamaguchi

Secretion of Saliva in X-Irradiated Rat Submandibular Glands

Abstract Takagi, K., Yamaguchi, K., Sakurai, T., Asari, T., Hashimoto, K. and Terakawa, S. Secretion of Saliva in X-Irradiated Rat Submandibular Glands. Radiat. Res. 159, 351–360 (2003). The mechanism of radiation-induced dysfunction in rat submandibular glands was investigated at the cellular level. After X irradiation (single dose, 15 Gy), a vacuolation in the acinar cells or an enlargement of the acinar lumen was observed as a typical morphological change for 2 weeks. As observed using a video-enhanced contrast differential interference contrast (VEC-DIC) microscope, exocytosis and shrinkage of the acinar cells induced by application of pilocarpine (100 μM) were markedly suppressed for 5 days and then recovered to 80% of the control levels. Using an immunohistochemical method, no significant change was observed in amylase distribution, but a marked loss of aquaporin 5 was found in the acinar cells after the irradiation. The extent and time course of pilocarpine-induced mobilization of intracellular Ca2+ did not change after the irradiation. We conclude that radiation-induced dysfunction in the salivary glands is due to an impairment of exocytosis and a reduction of water secretion. The loss of aquaporin 5 and possibly other membrane-fusion proteins in acinar cells may be the major mechanism underlying such a dysfunction.

Phosphoglyceride crystal deposition disease

An extremely rare phosphoglyceride deposition disease is reported. A healthy 62‐year‐old Japanese woman suffered from tumors that repeatedly appeared in injured soft tissues for more than 20 years. No immunologic disorders or abnormal laboratory data were found. Histology showed foreign body granulomas consisting of macrophages surrounding yellowish‐white crystals. The crystals were weakly positive by von Kossas method, were dissolved in 30% acetic acid with gas, and were easily dissolved in 0.1 N NaOH or potassium hydroxide, losing their crystal structure. Using a scanning electron microscopy X‐ray microanalyzer, phosphorus and calcium peaks were detected. Phosphoglycerides were detected by microscopic infrared spectrophotometry and microsampling mass spectrometry. The gold hydroxamic acid method for detecting phosphoglyceride showed strong positive staining in the crystals. Based on the above analyses, the deposited crystals were regarded as phosphoglyceride, which bound calcium as a counter ion. The crystals tended to be deposited at sites of injury, where macrophages had accumulated. The patient had received many injections of a medicine made from alcohol extract from bovine liver. We suspect that this medicine was related to the cause of the deposition as the deposition repeatedly appeared at the site of the injections.

The development of lesion imaging fluorescence diagnostic apparatus

We have developed the fluorescence diagnostic apparatus of oral lesion. In this study, we analyzed autofluorescence of SCC and leukoplakia. Both cases of SCC and leuk oplakia, we found two fluorescence peaks. In case of SCC, a major peak was at 628 nm and a smaller peak was at 668 nm. As regard to intensity, the maximal intensity of SCC was 18 times stronger than that of normal oral mucosa. In case of leukoplakia, a major peak was at 658 nm and smaller peak was at 627 nm. The maximal intensity of leukoplakia was five times stronger than that of normal oral mucosa. The results suggested that the autofluorescence diagnosis of oral lesion would be possible by new fluorescence diagnostic apparatus.