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

OBJECTIVE

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.