Figure 3. Pharmacological activation of cholinergic receptors mimics the effect of novelty exploration.
A, hippocampal slices obtained from stressed rats that received the cholinergic agonist carbachol (CCH; 0.2 mg kg−1, i.p.), before introduction into the home cage (S-HC rats) showed a stable LTP following HFS. Carbachol did not significantly affect LTP in slices from unstressed-home cage (US-HC) rats. B, comparison of the magnitude of LTP 50 min after HFS. C, animals that received stress plus carbachol were impaired in LFS-induced LTD in comparison with animals that received stress plus vehicle. D, comparison of the magnitude of LTD 50 min after LFS. E, representative immunoblots showing ERK1/2 phosphorylation after stress plus carbachol or vehicle treatment. The corresponding densitometric analysis is shown in F.