Differential Effects of Isoflurane and Propofol Anesthesia on Neurogenesis in Young and Aged Rats

Worldwide, millions of young and elderly patients receive procedures that could not be performed without the use of anesthetics. Unfortunately, emerging animal and human data suggest an association between exposure to general anesthesia and impairment of cognitive function in pediatric and geriatric patients. Recent laboratory data have shown that general anesthetics are potentially damaging to the developing and aging brain. However, the mechanism by which this happens is still unknown. General anesthetics affect learning and memory, a brain function involving neural plasticity. An important form of neural plasticity receiving attention is postnatal neurogenesis. This process is highly regulated and involved in hippocampal functions under physiological conditions. This dissertation hypothesizes that anesthetic induced alteration of postnatal neurogenesis may explain the cognitive impairment observed in some pediatric and geriatric patients after anesthesia. In order to accurately address this hypothesis, in the first portion of this dissertation, an animal model is used to examine the effects of two different anesthetics on cognition and new cell proliferation in young and aged rats. Furthermore, the second and third portion of this dissertation emphasizes on the effects of these two widely used anesthetics on each of the various stage of postnatal neurogenesis in young and aged rats