Development of spiroguanidine-derived α7 neuronal nicotinic receptor partial agonists.

We describe the synthesis of quinuclidine-containing spiroguanidines and their utility as α7 neuronal nicotinic acetylcholine receptor (nAChR) partial agonists. The convergent synthetic route developed for this study allowed for rapid SAR investigation and provided access to a structurally diverse set of analogs. A potent and selective α7 nAChR partial agonist, N-(6-methyl-1,3-benzoxazol-2-yl)-3',5'-dihydro-4-azaspiro[bicyclo[2.

MK-801 disrupts and nicotine augments 40 Hz auditory steady state responses in the auditory cortex of the urethane-anesthetized rat.

Patients with schizophrenia show marked deficits in processing sensory inputs including a reduction in the generation and synchronization of 40 Hz gamma oscillations in response to steady-state auditory stimulation. Such deficits are not readily demonstrable at other input frequencies. Acute administration of NMDA antagonists to healthy human subjects or laboratory animals is known to reproduce many sensory and cognitive deficits seen in schizophrenia patients.

A chamber and artificial dura method for long-term optical imaging in the monkey.

Optical imaging over extended periods of time in non-human primates presents serious challenges because the dura mater must be removed to expose the cortical surface. We present a novel nylon imaging chamber with a transparent artificial dura implant, which allows repeated, long-term optical recordings from the cortex. The cylinder of the chamber is inserted into a cranial trephination and held in place with a minimum of screws and acrylic cement.