Repeated or prolonged, but not short-term, general anesthesia during the early postnatal period causes long-lasting impairments in memory formation in various species. The mechanisms underlying long-lasting impairment in cognitive function are poorly understood. Here we showed that repeated general anesthesia in postnatal mice induces preferential apoptosis and subsequent loss of parvalbumin-positive inhibitory interneurons in the hippocampus. Each parvalbumin interneuron controls the activity of multiple pyramidal excitatory neurons, thereby regulating neuronal circuits and memory consolidation. Preventing the loss of parvalbumin neurons by deleting a pro-apoptotic protein MAPL (Mitochondrial Anchored Protein Ligase) selectively in parvalbumin neurons rescued anesthesia-induced deficits in pyramidal cell inhibition, and hippocampus-dependent long-term memory. Conversely, partial depletion of parvalbumin neurons in neonates was sufficient to engender long-lasting memory impairment. Thus, loss of parvalbumin interneurons in postnatal mice following repeated general anesthesia critically contributes to memory deficits in adulthood.
Patricia Soriano Roque, Carolina Thörn Perez, Mehdi Hooshmandi, Calvin Wong, Mohammad Javad Eslamizade, Shilan Heshmati, Nicole Brown, Vijendra Sharma, Kevin C. Lister, Vanessa Magalie Goyon, Laura E. Neagu-Lund, Cathy Shen, Nicolas Daccache, Hiroaki Sato, Tamaki Sato, Jeffrey S. Mogil, Karim Nader, Christos G. Gkogkas, Mihaela D. Iordanova, Masha Prager-Khoutorsky, Heidi M. McBride, Jean-Claude Lacaille, Linda Wykes, Thomas Schricker, Arkady Khoutorsky