Elevated P2x7r and P2x4r transcripts levels in the Flinders Sensitive Line Rats, a genetic animal model of depression

Abstract

P2x7 and P2x4 receptors (P2x7R and P2x4R, respectively) are ligand-gated ion channels activated by adenosine triphosphate (ATP), which have been associated to dysfunctional processes in stress responses linked to depression, such as neurotransmitter release, cognition, sleep, energy, appetite, immune and endocrine dysfunction. Clinical studies indicate that polymorphisms in the P2x7r gene results in increased susceptibility for development of depression. Existing studies have investigated the role of P2x7R and P2x4R in animal models based on stress exposure. Therefore, the present work aimed to investigate the transcript and protein levels of these receptors in a genetic animal model of depression, the Flinders Sensitive Line (FSL) and its control group, the Flinders Resistant Line (FRL) rats. We found that FSL rats have increased transcript levels of P2x7R and P2x4R in frontal cortex (FC), ventral and dorsal hippocampus (vHip and dHip, respectively) compared to FRL rats. There were no alterations in the protein levels in the FC and dHip, but the P2x7R was lower in FSL than in FRL rats in the vHip. The results suggest that increased transcripts levels of P2x7r and P2x4r in the FSL rats may contribute to the stress-susceptibility observed in these animals.