LONG-LASTING EFFECTS OF EARLY POSTNATAL DYSFUNCTION OF THE BRAIN MUSCARINIC CHOLINERGIC SYSTEM ON LEARNING AND MEMORY AND ADULT HIPPOCAMPAL NEUROGENESIS.

Aim: The present investigation aimed to explore in rats the early postnatal dysfunction of the brain muscarinic cholinergic system (EPDMChS) during the most vulnerable period of postnatal development, as the possible main factor for changes in adult hippocampal neurogenesis and disorders in hippocampus-dependent spatial learning and memory.

Methods: White inbred rats (n=15 in each group) were used. EPDMCHS was produced by a new method, which includes early postnatal blocking of M1-M5 muscarinic acetylcholine receptors in the rat pups, using subcutaneous injection of Scopolamine during postnatal days 7-28. Control rat pups received the same volume as Saline. Researches were started in adult age (2.5-3 months).

Results And Conclusion: It was shown for the first time that EPDMCHS exerts long-lasting effects manifested in adult age in the impairment of hippocampal neurogenesis and significant deterioration of spatial long-term declarative memory in the MWM. The possible causal link between the EPDMCHS and two types of resulting disorders is underlined.