Abhishek Kumar, Kumar Tarun, Shekhar Ravi, Sakshi Pooja, Kumar Pooja, Kumar Amritesh
Physiology, Indira Gandhi Institute of Medical Sciences, Patna, IND.
Biochemistry, Indira Gandhi Institute of Medical Sciences, Patna, IND.
Cureus. 2024 Dec 19;16(12):e76038. doi: 10.7759/cureus.76038. eCollection 2024 Dec.
Background Lactate, once considered merely a byproduct of anaerobic metabolism, is now recognized as a crucial neuromodulator in the brain, particularly during high-energy demands. Recent studies have explored its role in neuroprotection, cognitive enhancement, and neural plasticity. This study investigates the effects of elevated blood lactate levels, induced by acute exercise, on visual evoked potentials (VEPs), which reflect neural activity in the visual cortex. Methodology This interventional study was performed in the Department of Physiology, Indira Gandhi Institute of Medical Sciences, Patna, BR, IND. Fifty healthy male subjects aged 18 to 40 years, participated in the study. Baseline blood lactate levels and VEP were recorded after 30 minutes of rest. Subjects then performed aerobic exercise until exhaustion, following the Bruce protocol. Blood lactate levels and VEPs were measured immediately at the end of exercise and again at 10 and 20 minutes post-exercise. Visual evoked potentials (the N75, P100, and N145 waves) were recorded according to the International 10-20 system, using the MEP Neurosoft four-channel machine (Neurosoft, Ivanovo, RUS). Data were analyzed using repeated measures ANOVA, Pearson's correlation, and linear regression via SPSS Statistics version 29.0.2.0 (IBM Corp, Armonk, NY, USA). Results Post-exercise, blood lactate levels were raised, which was statistically significant. The VEP analysis showed a statistically significant decrease in P100 latency immediately after exercise, which correlated with the rise in lactate levels having a p-value <0.001. The increase in N145 latency at 10 minutes post-exercise was statistically significant, which correlated with changes in lactate levels. The N75 latency exhibited a statistically significant decrease at 10 minutes post-exercise, though it had no statistically significant correlation with lactate levels. Conclusion The study demonstrates that elevated blood lactate levels post-exercise influence VEPs, particularly by decreasing P100 latency and increasing N145 latency. These findings suggest that elevated lactate levels post-exercise may enhance primary visual cortex activity, possibly as a protective mechanism to maintain essential visual processing. However, this enhancement may impair communication with extrastriate areas, potentially reducing the accuracy of perceiving complex visual features such as color, depth, and motion.
背景 乳酸，曾被认为仅仅是无氧代谢的副产物，现在被公认为大脑中一种关键的神经调节剂，尤其是在高能量需求期间。最近的研究探讨了其在神经保护、认知增强和神经可塑性方面的作用。本研究调查急性运动诱导的血液乳酸水平升高对视觉诱发电位（VEP）的影响，VEP反映视觉皮层的神经活动。
方法 本干预性研究在印度巴特那英迪拉·甘地医学科学研究所生理学系进行。50名年龄在18至40岁的健康男性受试者参与了研究。休息30分钟后记录基线血液乳酸水平和VEP。然后受试者按照布鲁斯方案进行有氧运动直至 exhaustion。运动结束时立即测量血液乳酸水平和VEP，并在运动后10分钟和20分钟再次测量。根据国际10 - 20系统，使用MEP Neurosoft四通道机器（Neurosoft，俄罗斯伊万诺沃）记录视觉诱发电位（N75、P100和N145波）。通过SPSS Statistics 29.0.2.0版本（美国纽约州阿蒙克IBM公司）使用重复测量方差分析、皮尔逊相关性分析和线性回归对数据进行分析。
结果 运动后，血液乳酸水平升高，具有统计学意义。VEP分析显示运动后立即P100潜伏期有统计学意义的降低，其与乳酸水平升高相关，p值<0.001。运动后10分钟N145潜伏期增加具有统计学意义，其与乳酸水平变化相关。运动后10分钟N75潜伏期有统计学意义的降低，尽管其与乳酸水平无统计学意义的相关性。
结论 该研究表明运动后血液乳酸水平升高会影响VEP，特别是通过降低P100潜伏期和增加N145潜伏期。这些发现表明运动后升高的乳酸水平可能增强初级视觉皮层活动，可能作为维持基本视觉处理的一种保护机制。然而，这种增强可能会损害与纹外区域的通信，可能降低感知颜色、深度和运动等复杂视觉特征的准确性。
