Matic Damir B, Lee Ting Y, Wells R Glenn, Gan Bing S
London, Ontario, Canada From the Division of Plastic and Reconstructive Surgery and Department of Medical Biophysics, University of Western Ontario.
Plast Reconstr Surg. 2007 Dec;120(7):1823-1833. doi: 10.1097/01.prs.0000287135.17291.2f.
Botulinum toxin type A is approved by the U.S. Food and Drug Administration for the treatment of facial rhytides. However, the complete spectrum of action of botulinum toxin A has not yet been completely defined. Little is known about the metabolism of muscle after botulinum toxin A injection. This information may give insight into the additional effects botulinum toxin A may have on muscle. The authors assessed the influence of botulinum toxin A on the metabolism of muscle using dynamic investigative techniques.
Twenty New Zealand White rabbits were divided into control, paralysis, and sham groups. Masseter muscle paralysis was achieved with botulinum toxin A. Dynamic computed tomographic and positron emission tomographic scans were obtained. Masseter muscle blood flow, blood volume, permeability surface, and mean transit time and glucose uptake were measured.
Eighteen animals completed the study. Masseter blood perfusion showed consistent results across all parameters. Blood flow, blood volume, and permeability surface were significantly increased at weeks 4 and 8 on the paralyzed side. Mean transit time at week 4 was decreased on the paralyzed side. Positron emission tomographic scans showed that injected muscles in the botulinum toxin A group tended to have increased glucose uptake compared with untreated muscles.
Botulinum toxin A injection increases muscle blood perfusion parameters and glucose uptake for a transient period. This increase is similar in duration to the known interval of botulinum toxin A-induced paralysis. These changes have been identified in a dynamic fashion and may represent changes in calcitonin gene-related peptide release.
A型肉毒毒素已获美国食品药品监督管理局批准用于治疗面部皱纹。然而，A型肉毒毒素的完整作用谱尚未完全明确。关于注射A型肉毒毒素后肌肉的代谢情况知之甚少。这些信息可能有助于深入了解A型肉毒毒素对肌肉的其他作用。作者使用动态研究技术评估了A型肉毒毒素对肌肉代谢的影响。
将20只新西兰白兔分为对照组、麻痹组和假手术组。用A型肉毒毒素使咬肌麻痹。进行动态计算机断层扫描和正电子发射断层扫描。测量咬肌的血流量、血容量、通透性表面积、平均通过时间和葡萄糖摄取量。
18只动物完成了研究。咬肌的血液灌注在所有参数上均显示出一致的结果。麻痹侧在第4周和第8周时血流量、血容量和通透性表面积显著增加。麻痹侧第4周的平均通过时间缩短。正电子发射断层扫描显示，与未治疗的肌肉相比，A型肉毒毒素组中注射药物的肌肉葡萄糖摄取量有增加的趋势。
注射A型肉毒毒素可在短时间内增加肌肉的血液灌注参数和葡萄糖摄取量。这种增加的持续时间与已知的A型肉毒毒素诱导麻痹的间隔时间相似。这些变化已通过动态方式得以确定，可能代表降钙素基因相关肽释放的变化。
