Rationale and Objectives: This study is aimed at investigating neurochemical changes in scopolamine (SCP)-induced memory impairment using spatially localized invivo magnetic resonance spectroscopy (MRS) of the hippocampus. Materials and Methods: Four groups of mice (eight mice per group) were scanned after the injection of different SCP doses: 0, 1, 3, and 5 mg/kg (intraperitoneally). All the animals received 1H MRS of their hippocampus at two time intervals: 30minutes and 72hours after SCP injection. Results: This work demonstrated that the doses of 3 mg/kg SCP or higher reduce the concentration of total choline-containing compounds, and these levels returned to baseline after 72hours. These results are consistent with observations made by others using more invasive brain dialysis approaches. The levels of glutamate and glutamic compounds (glutamate+glutamine) were slightly changed at 3 and 5mg/kg SCP dose, but the differences were not statistically significant (P>.05). These findings suggest that SCP produces transient, invivo measurable alterations in the cholinergic system in the hippocampus. Conclusions: On this basis, we conclude that invivo MRS is a feasible noninvasive method to probe aspects of the alterations induced by SCP in the cholinergic neurotransmission pathways in both animal models and human studies of memory impairment.
- Cholinergic system
- Memory impairment
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging