Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA, 02115, USA.
Sci Rep. 2023 Oct 9;13(1):17002. doi: 10.1038/s41598-023-43920-2.
Cerebrospinal fluid (CSF) is crucial for maintaining neuronal homeostasis, providing nutrition, and removing metabolic waste from the brain. However, the relationship between neuronal activity and CSF solute transport remains poorly understood. To investigate the effect of regional neuronal activity on CSF solute transport, Sprague-Dawley rats (all male, n = 30) under anesthesia received an intracisternal injection of a fluorescent tracer (Texas Red ovalbumin) and were subjected to unilateral electrical stimulation of a forelimb. Two groups (n = 10 each) underwent two different types of stimulation protocols for 90 min, one including intermittent 7.5-s resting periods and the other without rest. The control group was not stimulated. Compared to the control, the stimulation without resting periods led to increased transport across most of the cortical areas, including the ventricles. The group that received intermittent stimulation showed an elevated level of solute uptake in limited areas, i.e., near/within the ventricles and on the ventral brain surface. Interhemispheric differences in CSF solute transport were also found in the cortical regions that overlap with the forelimb sensorimotor area. These findings suggest that neuronal activity may trigger local and brain-wide increases in CSF solute transport, contributing to waste clearance.
脑脊液（CSF）对于维持神经元内环境稳定、提供营养和清除大脑代谢废物至关重要。然而，神经元活动与 CSF 溶质转运之间的关系仍知之甚少。为了研究局部神经元活动对 CSF 溶质转运的影响，麻醉状态下的 Sprague-Dawley 大鼠（均为雄性，n=30）接受了脑室内荧光示踪剂（Texas Red 卵清蛋白）注射，并接受了单侧前肢电刺激。两组（每组 n=10）接受了两种不同类型的刺激方案 90 分钟，一种包括 7.5 秒的间歇休息期，另一种没有休息期。对照组未接受刺激。与对照组相比，无休息期的刺激导致大部分皮质区域的转运增加，包括脑室。接受间歇性刺激的组在有限的区域表现出更高的溶质摄取水平，即在脑室附近/内部和脑腹表面。在与前肢感觉运动区重叠的皮质区域中，也发现了 CSF 溶质转运的半球间差异。这些发现表明，神经元活动可能触发 CSF 溶质转运的局部和全脑增加，有助于清除废物。
