Intragastric administration of prednisone acetate induced impairment of hippocampal long-term potentiation

Prednisone acetate (PA) has many adverse side effects despite the fact that oral administration of PA is widely administrated in the clinic. However, it is unknown whether PA can cause hippocampal long-term potentiation (LTP) impairment. Therefore, in our study, PA (5 mg/kg center dot d) through intragastric administration (gavage) was applied to establish a model of impaired hippocampal LTP in C57BL/6 mice, and the method was evaluated by comparing with another method to establish LTP impairment through subcutaneous injection of corticosterone (CORT, 50 mg/kg center dot d). First, our results showed PA caused a more significant decrease in population spike (PS, %) after high-frequency stimulation (HFS) than CORT, demonstrating PA induced impairment of hippocampal LTP more successfully than CORT. Second, PA caused poorer performance of memory than CORT. Third, PA caused more serious lesions and loss of the granule cell in the dentate gyrus than CORT. Finally, PA caused lower levels of glutamic acid (Glu), N-methyl-D-aspartate receptors (NMDARs) and gamma-aminobutyric acid (GABA) than CORT. All in all, PA (5 mg/kg center dot d) through intragastric administration (gavage) induced LTP impairment in the hippocampus more successfully than CORT. The neuronal lesions in the dentate gyrus and the consequent decrease of Glu and NMDARs (especially NMDAR2A) may be the cause of LTP impairment.