Changes of theta oscillation of prelimbic cortex in heroin-induced CPP rats

Abstract

To investigate the relationship between the changes of neural oscillations and the drug-seeking motivation,record the telemetric local field potentials (LFPs) of the prelimbic cortex (PrL) in the latency of drug-seeking behavior of conditioned place preference (CPP) rats induced by heroin. The recording electrode was stereotactically implanted intothe PrL cortex of rats. The animals were then randomly divided into operation-only control and heroin-induced CPP groups, respectively. A CPP video system in combination with awireless telemetry device was used for recording LFPs when the rats shuttled between black-white chamber for drug-seeking. The LFPs were analyzed by fast Fourier transform (FFT) and wavelet packet extraction. Compared with operation-only control group, the LFPs recorded in PrL area of heroin-induced CPP group of rat during black-white chamber shuttling showed that the percentage of θ rhythm were increased in right and left PrL, the percentage of γ3 rhythm was increased in left PrL, the phase-amplitude coupling of θ and γ3 was increased in left PrL. After MK-801 Maleate micro injection to PrL area,drug-seeking behavior of rat was markedly reduced and the percentage of θ oscillation was depressed,the phase-amplitude coupling of θ and γ3 was depressed in left PrL compared with operation-only control group. These results suggest that increase of θ oscillations of PrL area may be related to the drug-seeking motivation and behavior launching in heroin-induced CPP groups of rat. The changes of θ oscillations also have close relationship with glutamatergic neuron and the receptor of it on PrL area.