|Budget Amount *help
¥3,200,000 (Direct Cost : ¥3,200,000)
Fiscal Year 1999 : ¥1,600,000 (Direct Cost : ¥1,600,000)
Fiscal Year 1998 : ¥1,600,000 (Direct Cost : ¥1,600,000)
One hundred Wistar rats and 100 spontaneous diabetes mellitus (GK) rats were included in this study, and divided into 4 groups ; J-1 : non-stress Wistar rats, J-2 : restraint-stress Wistar rats, G-1 : non-stress GK rats, G-2 : restrain-stress GK rats. A ligation was done around the 2nd molar in the maxillary right sides. The rats in the stress group (J-2 and G-2) exposed to a stressful condition by the use of wire mesh for 12 hours during 10 days. Ten rats in each group were sacrificed on days 2, 4, 6, 8, and 10. At the time of sacrifice, the peripheral blood was taken and the thymus and the maxillae were removed. The maxillae were fixed, decalcified, embedded, and sectioned serially. The furcation area of the 2nd maxillary molars were examined histologically and histometrically.
The body weights in the stress group were reduced than those of the non-stress group(J-1 and G-1). The fasten blood glucose in the stress group were significantly increased. The concentrations of plasma adrenocorticotropic hormone and adrenaline in J-2 were significantly increased than those of J-1. On the other hand, the same concentrations in G-2 were significantly increased than those of G-1 on days 2, 4, however, significantly reduced after the 6th day. The thymus in the stress group was significantly atrophied. Numerous tufts on nerve fibers that may indicate a neurogenic inflammation were observed in the furcation area of J-2 histologically. But there were not such findings in G-2. The alveolar bone resorption in the stress group on days 8, and 10 were significantly greater than that of non-stress group histometrically. The results of this study indicated that the restraint stress may be one of the risk factors for experimental periodontitis. However, in diabetic rats, the mechanism affects the periodontium under the stressful condition may differ from normal rats.