Lapchak P A, Salgado K F, Chao C H, Zivin J A
University of California San Diego, Department of Neuroscience, MTF 316, 9500 Gilman Drive, La Jolla, CA 92093-0624, USA.
Neuroscience. 2007 Sep 21;148(4):907-14. doi: 10.1016/j.neuroscience.2007.07.002. Epub 2007 Jul 12.
Photon or near-infrared light therapy (NILT) may be an effective neuroprotective method to reduce behavioral dysfunction following an acute ischemic stroke. We evaluated the effects of continuous wave (CW) or pulse wave (P) NILT administered transcranially either 6 or 12 h following embolization, on behavioral outcome. For the studies, we used the rabbit small clot embolic stroke model (RSCEM) using three different treatment regimens: 1) CW power density of 7.5 mW/cm(2); 2) P1 using a frequency of 300 mus pulse at 1 kHz or 3) P2 using a frequency of 2 ms pulse at 100 Hz. Behavioral analysis was conducted 48 h after embolization, allowing for the determination of the effective stroke dose (P(50)) or clot amount (mg) that produces neurological deficits in 50% of the rabbits. Using the RSCEM, a treatment is considered beneficial if it significantly increases the P(50) compared with the control group. Quantal dose-response analysis showed that the control group P(50) value was 1.01+/-0.25 mg (n=31). NILT initiated 6 h following embolization resulted in the following P(50) values: (CW) 2.06+/-0.59 mg (n=29, P=0.099); (P1) 1.89+/-0.29 mg (n=25, P=0.0248) and (P2) 1.92+/-0.15 mg (n=33, P=0.0024). NILT started 12 h following embolization resulted in the following P(50) values: (CW) 2.89+/-1.76 mg (n=29, P=0.279); (P1) 2.40+/-0.99 mg (n=24, P=0.134). At the 6-h post-embolization treatment time, there was a statistically significant increase in P(50) values compared with control for both pulse P1 and P2 modes, but not the CW mode. At the 12-h post-embolization treatment time, neither the CW nor the P1 regimens resulted in statistically significant effect, although there was a trend for an improvement. The results show that P mode NILT can result in significant clinical improvement when administered 6 h following embolic strokes in rabbits and should be considered for clinical development.
光子或近红外光疗法（NILT）可能是一种有效的神经保护方法，可减少急性缺血性中风后的行为功能障碍。我们评估了栓塞后6小时或12小时经颅给予连续波（CW）或脉冲波（P）NILT对行为结果的影响。在研究中，我们使用兔小血栓栓塞性中风模型（RSCEM），采用三种不同的治疗方案：1）CW功率密度为7.5 mW/cm²；2）P1，频率为1 kHz的300 μs脉冲；或3）P2，频率为100 Hz的2 ms脉冲。栓塞后48小时进行行为分析，以确定在50%的兔子中产生神经功能缺损的有效中风剂量（P50）或血栓量（mg）。使用RSCEM，如果与对照组相比，治疗能显著提高P50，则认为该治疗有益。定量剂量反应分析显示，对照组的P50值为1.01±0.25 mg（n = 31）。栓塞后6小时开始的NILT产生了以下P50值：（CW）2.06±0.59 mg（n = 29，P = 0.099）；（P1）1.89±0.29 mg（n = 25，P = 0.0248）和（P2）1.92±0.15 mg（n = 33，P = 0.0024）。栓塞后12小时开始的NILT产生了以下P50值：（CW）2.89±1.76 mg（n = 29，P = 0.279）；（P1）2.40±0.99 mg（n = 24，P = 0.134）。在栓塞后6小时的治疗时间，与对照组相比，脉冲P1和P2模式的P50值有统计学显著增加，但CW模式没有。在栓塞后12小时的治疗时间，CW和P1方案均未产生统计学显著效果，尽管有改善趋势。结果表明，在兔栓塞性中风后6小时给予P模式NILT可导致显著的临床改善，应考虑用于临床开发。
