Sleep Molecular Laboratory

Dr. Dheeraj Pelluru - Electrophysiology

As part of our strategy to identify the network underlying sleep, we monitor the activity of neurons in areas implicated in sleep.  In the past we have used c-FOS as a marker of neuronal activity, but it is at best an indirect indicator of the behavior of the neuron.  To provide real-time assessment of the behavior of neurons it is best to use electrophysiology.  Stephen Thankachan monitored the activity of neurons in the vlPAG in orexin knockout mice (Thankachan et al., 2009).  These mice are an animal model of narcolepsy and Stephen is the first to record the activity of single neurons in this model (see photo).  He discovered that the majority of neurons in the vlPAG are active during wake which supports ours and Luppi’s hypothesis that activity of these neurons during wake inhibits REM sleep.  However, he also found that 10% of neurons are selectively active only during REM sleep indicating that REM sleep generator neurons are also present in the vlPAG. 

Action potential of wake active neurons in the pons of orexin knockout mice.  The figure represents the summation of seven action potentials of the same neuron.