The expression of the TrkA and TrkB high-affinity neurotrophin receptors in the rat hippocampus after intracerebroventricular administration of Aβ(25–35)

We studied the changes in the expression of high-affinity TrkA and TrkB receptors of the nerve-growth factor and brain-derived neurotrophic factor in the rat hippocampus at different time points after the administration of Aβ(25–35) into the lateral cerebral ventricles. Studies on TrkA and TrkB expression were performed using immunohistochemistry and the method of the real-time polymerase chain reaction. We found that intracerebroventricular administration of Aβ(25–35) to rats resulted in long-term alterations in the system of neurotrophic signaling in the hippocampus. Expression of the TrkA receptor increased 28 days after treatment, whereas expression of the TrkB receptor increased 12 days and then decreased by 28 days after the treatment. Thus, alterations in neurotrophin signaling may be involved in the mechanisms that are responsible for Aβ(25–35)-induced impairment of hippocampal functions in rats.