Neurons expressing distinct receptors in ventral lateral periaqueductal gray exhibit different modulatory roles in pain and itch sensation

Ventral lateral periaqueductal gray(vIPAG)is an essential transmit node in descending transmission pathway.However,whether neurons expressing different receptors in vIPAG paly distinct roles in nociception and pruriception remains elusive.To evaluate the possible effects of different neuroactive substances in vlPAG,cannula was implanted in the right side of the vIPAG.In the present study,a-amino 3-hydroxy-5-methyl-4-isoxazole-propionic acid(AMPA)receptor antagonist CNQX,N-methyl-D-aspartic acid(NMDA)receptor antagonist AP-5,Y-aminobutyric acid A(GABAs)receptor antagonist picrotoxin(PTX),μ-opioid receptor antagonist CTOP and calcitonin gene-related peptide(CGRP)antagonist CGRP8-37 were utilized.