Acetylcholine/metabolism; Glutamic Acid/metabolism; Prefrontal Cortex/metabolism; Receptors, Nicotinic/metabolism; Synaptic Transmission/physiology; Afferent Pathways/anatomy & histology; Afferent Pathways/metabolism; Afferent Pathways/surgery; Animals; Denervation; Excitatory Postsynaptic Potentials/drug effects; Excitatory Postsynaptic Potentials/genetics; Female; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Nicotinic Agonists/pharmacology; Presynaptic Terminals/metabolism; Receptors, Nicotinic/drug effects; Receptors, Nicotinic/genetics; Signal Transduction/physiology; Synapses/genetics; Synapses/metabolism; Thalamus/anatomy & histology; Thalamus/metabolism; Thalamus/surgery; Time Factors; Ventral Tegmental Area/anatomy & histology; Ventral Tegmental Area/metabolism; Ventral Tegmental Area/surgery; alpha7 Nicotinic Acetylcholine Receptor