Nimodipine prevents the in vivo decrease in hippocampal extracellular acetylcholine produced by hypobaric hypoxia

摘要: Hypoxia decreases acetylcholine (ACh) synthesis and release in vitro, ACh vivo; however, its effect on extracellular concentration of vivo is not known. The calcium channel blocker nimodipine a cerebrovascular dilator which also increases vivo. Therefore, it may provide protection from the effects hypobaric hypoxia cholinergic system either via vascular function or by direct action nervous system. This study examined choline levels, as measured microdialysis, well under hypoxia. Microdialysis guide cannulae were implanted into hippocampal region male Fischer rats so that probes would sample CA1 DG regions. Animals then exposed for eight hours to simulated altitude 5,500 m (18,000 ft) tested at sea level an equivalent duration. HPLC with electrochemical detection was used analysis dialysates. At levels placebo-treated group significantly lower than values. decrement reversed administered i.p. immediately preceding ascent (10 mg/kg) 250 min post-altitude mg/kg). These data suggest detrimental function.