Mitogen-activated protein kinase in the amygdala plays a critical role in lithium chloride-induced taste aversion learning

作者：Kwon Bumsup; Houpt Thomas A^*

来源：Neurobiology of Learning and Memory, 2012, 97(1): 132-139.

DOI：10.1016/j.nlm.2011.10.005

• Mitogen-activated protein kinase
• Conditioned taste aversion
• Lithium chloride
• SL327
• Central nucleus of the amygdala
• Nucleus of the solitary tract

The intracellular mitogen-activated protein kinase (MAPK) pathway in the brain is necessary for the formation of a variety of memories including conditioned taste aversion (CIA) learning. However, the functional role of MAPK activation in the amygdala during lithium chloride (LiCl)-induced CIA learning has not been established. In the present study, we investigated if local microinjection of SL327, a MAPK kinase inhibitor, into the rat amygdala could alleviate LiCl-induced CTA learning. Our results revealed that acute administration of a high dose of LiCl (0.15 M, 12 ml/kg, i.p.) rapidly increased the level of phosphorylated MAPK (pMAPK)-positive cells in the central nucleus of the amygdala (CeA) and nucleus of the solitary tract (NTS) of rats as measured by immunohistochemistry. Local microinjection of SL327 (1 mu g/0.5 mu l/hemisphere) into the CeA 10 min before LiCl administration decreased both the strength of LiCl-induced CIA paired with 0.125% saccharin and the level of LiCl-induced pMAPK-positive cells in the CeA, but not in the NTS. Our data suggest that the intracellular signaling cascade of the MAPK pathway in the CeA plays a critical role in the processing of visceral information induced by LiCl for CIA learning.

• 出版日期2012-1