Li, XiaohuaFriedman, Ari BRoh, Myoung-SunJope, Richard S2023-05-222023-05-222005-01-102017-02-01https://repository.upenn.edu/handle/20.500.14332/2671Glycogen synthase kinase-3 (GSK3) is a crucial enzyme contributing to the regulation of neuronal structure, plasticity and survival, is implicated as a contributory factor in prevalent diseases such as Alzheimer’s disease and mood disorders and is regulated by a wide range of signaling systems and pharmacological agents. Therefore, factors regulating GSK3 in vivo are currently of much interest. GSK3 is inhibited by phosphorylation of serine-9 or serine-21 in GSK3β and GSK3α, respectively. This study found that accurate measurements of phospho-Ser-GSK3 in brain are confounded by a rapid post-mortem dephosphorylation, with ~90% dephosphorylation of both GSK3 isoforms occurring within 2 min post-mortem. Furthermore, three anesthetics, pentobarbital, halothane and chloral hydrate, each caused large in vivo increases in the serine phosphorylation of both GSK3β and GSK3α in several regions of mouse brain. Thus, studies of the phosphorylation state of GSK3 in brain, and perhaps in other tissues, need to take into account post-mortem changes and the effects of anesthetics and there is a direct correlation between anesthesia and high levels of serine-phosphorylated GSK3.This is the peer reviewed version of the following article: J Neurochem. 2005 February ; 92(3): 701–704., which has been published in final form at http://dx.doi.org/10.1111/j.1471-4159.2004.02898.x. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving (https://authorservices.wiley.com/author-resources/Journal-Authors/licensing-and-open-access/open-access/self-archiving.html).anesthesiaglycogen synthase kinase-3pentobarbitalpost-mortem intervalArticle