ABSTRACT
Objective To investigate the relationship between the rat depression behaviors induced by chronically unpredicted stress (CUS) with interleukin-1β (IL-1β),interleukin-6 (IL-6) protein expression and indole-2,3-dioxygenase (IDO) mRNA and protein expression.Methods Thirty male Sprague Dawley (SD)rats were divided into the control group (CG) and model group (MG).The solitary raise combined with CUS 28 d continued stimulus was used to establish the rat depression model.The open field test (OFT) and the force swimming test (FST) were used to evaluate the rat depression behaviors;qRT-PCR was used to determine the mRNA expression of IDO in hippocampus and cortex;Western blot was used to determine the protein expressions of IL-1β,IL-6 and IDO in hippocampus and cortex.Results Compared with the CG group,the OFT score in the rats of the MG group was significantly decreased(P＜0.01),the immobility time in FST was significantly extended (P＜0.00),the expression of IDO mRNA in hippocampus and cortex was significantly increased (P＜0.01) and the protein expression of IL-1β,IL-6 and IDO in hippocampus and cortex was significantly increased (P＜0.05).Conclusion The rat depression behaviors induced by CUS may be associated with the increase of intracerebral inflammatory cytokine expression and inducing IDO over-expression.
ABSTRACT
The determination of amino acids with actions like neurotransmitters or modulators has been increasingly important for diagnosis in many neuropsychiatric diseases. A rapid and simple high-performance liquid chromatography with fluorescence detection method was developed for simultaneous determination of seven amino acids: aspartate (Asp), glutamate (Glu), serine (Ser), glutamine (Gln), glycine (Gly), taurine (Tau) and γ-aminobutyric` acid (GABA). Homoserine was used as an internal standard. The analysis was performed on a BDS column with methanol and 50 mm sodium acetate solution (pH 6.5) using a simple gradient elution. Several parameters of the developed method were validated including linearity, accuracy, precision, extraction recovery and stability, which were within the acceptable range. The method was successfully applied to determination of real samples: hippocampus and cortex in depressed rats exposed to chronically unpredictable stress in order to study if there existed differences in the seven amino acids levels between depressed rats and control. The results showed that Asp, Gly, Tau and GABA significantly decreased with increasing Gln in the hippocampus of depressed rats, compared with that of the control group, among which obviously lower level of Asp and higher level of Gln in cortex were observed. The analytical method and the results could be useful for clinical diagnosis and further insight into pathophysiological mechanism of depression.
