Sex Differences in Nicotinic Currents of Layer VI Neurons of Prefrontal Cortex During Development

• Main Author: Alves, Nyresa
• Other Authors: Lambe, Evelyn K.
• Language: en_ca
• Published: 2009
• Subjects: prefrontal cortex; nicotine; sex difference; electrophysiology; development; progesterone; 0719
• Online Access: http://hdl.handle.net/1807/18137

There is a large sex difference in the prevalence of attention deficit disorder; yet, little is known about sex differences in prefrontal attention circuitry. We investigated sex differences in the developmental nicotinic excitation of corticothalamic layer VI neurons, which play an important role in attention. Using whole cell recording in prefrontal brain slices, we examined the inward currents elicited by nicotinic stimulation in rodents. We found a prominent sex difference in the currents during the first postnatal month when males had significantly greater α4β2* nicotinic currents. Immunohistochemical analysis of α4YFP mice revealed no sex difference in the pattern or proportion of YFP-positive neurons in layer VI. Further electrophysiological experiments revealed that progesterone is able to rapidly and significantly suppress nicotinic currents in layer VI neurons. This is the first illustration at a cellular level that prefrontal attention circuitry is differently excited by nicotinic stimulation in males and females during development.