Fig. 1: PV neurons control network oscillations.
From: Fast-spiking parvalbumin-positive interneurons in brain physiology and Alzheimer’s disease
A PV neurons (blue) in the CA1 region of the hippocampus control network activity via feedback inhibition (1), feedforward inhibition (2) and autaptic self-inhibition (3). Their fast-spiking properties and fast GABA release onto pyramidal neurons (gray) are due to the expression of specific ion channels and calcium sensors. Nav1.1 sodium and Kv1 and Kv3 potassium channel subunits enable high frequency firing of PV neuron in response to depolarizing currents while HCN channels facilitate action potential propagation. P/Q-type calcium channel subunits and synaptotagmin 2 allow for precise GABA release resulting in accurately timed inhibitory postsynaptic currents in pyramidal neurons. B CA1 PV and pyramidal neuron spikes are time-locked with theta-nested gamma oscillations during learning and memory. The oscillatory wave depends on PV neurons firing periodically at gamma frequencies in the trough of the theta wave followed by pyramidal neuron firing at the peak of the theta wave. C During rest and sleep, high frequency PV neuron firing is phase-coupled to the oscillatory cycle of sharp-wave ripples oscillations.
