Smaller Sized Inhaled Anesthetics have More Potency on Senescence-Accelerated Prone-8 Mice Compared with Senescence-Resistant-1 Mice

Background: Increasingly more aged people with Alzheimer's disease (AD) must undergo surgery with general anesthesia for various reasons. Knowing the potency of common inhaled anesthetics on AD patients is important to minimize the quantity of inhaled anesthetics. Previous studies indicated that transgenic AD mice were more resistant to the common inhaled anesthetics than were wild-type mice. However, transgenic AD mice are associated with early-onset familial AD, which accounts for only 5% of the total AD patients in the clinic. Confirming the results using other animal AD models is still necessary. Objective: The aim of this study was to evaluate the potency of common inhaled anesthetics in another AD animal model, the senescence-accelerated mouse prone-8 (SAMP-8) model. Methods: The minimum alveolar concentration (MAC) was measured by tail clamping in the SAMP-8 and senescence-resistant-1 (SAMR-1) mice at 4, 6, 8, and 10 months of age (n = 13). A two-way ANOVA (age and strain as the two factors) was used to analyze the difference. Results: The statistical results showed that both the age and strain factors had significant effects on the MAC values. The MAC of the SAMP-8 mice was significantly lower than that of the SAMR-1 mice for the three inhaled anesthetics. The MAC values of the SAMP-8 mice decreased significantly with aging. Conclusions: The SAMP-8 mice were more sensitive to the three inhaled anesthetics than were the SAMR-1 mice.