1999 Volume 13 Issue 3 Pages 166-174
In order to verify the influence of tooth loss and masticatory alterations on cholinergic neurons in aged rat brain, 36 Wistar male old rats were divided into the following groups: a control group (fed with a solid diet), a soft diet group (fed with a powder diet containing the same components as the solid one), and a molarless group (all molars were removed at 25 weeks and then the rats were fed with a powder diet). Immunohistochemical and biochemical studies were performed.
The results obtained were as follows.
1. The number of choline acetyltransferase (ChAT)-positive neurons in the nucleus of the diagonal band/medial septal nucleus showed statistically significant differences between the control and the molarless group (p<0.01).
2. The number of ChAT-positive neurons in the nucleus of the diagonal band/medial septal nucleus showed no statistically significant differences between the control and the soft diet groups.
3. Acetylcholine (ACh) concentrations in the hippocampus showed statistically significant differences between the control and the molarless group (p<0.05).
4. Choline (Ch) concentrations in the hippocampus showed no statistically significant differences between the control and the molarless group.
Tooth loss and masticatory alterations in rat caused a decrease in ChAt-positive neurons in the nucleus of the diagonal band/medial septal nucleus by a change of afferent. A decrease in ChAT-positive neurons in the nucleus of the diagonal band/medial septal nucleus caused a decline in ACh concentrations in the hippocampus.
