Time Course Analysis of the Effects of Botulinum Neurotoxin Type A on Pain and Vasomotor Responses Evoked by Glutamate Injection into Human Temporalis Muscles

Toxins

Larissa Bittencourt da Silva¹  Dolarose Kulas¹  Ali Karshenas²  Brian E. Cairns¹  Flemming W. Bach²  Lars Arendt-Nielsen¹ 

[1] Center for Sensory-Motor Interaction (SMI), Department of Health Science and Technology, Aalborg University, Aalborg DK-9220, Denmark; E-Mails:;Neurology Department, Aalborg University Hospital, Aalborg DK-9100, Denmark; E-Mails:

关键词: botulinum neurotoxin type A;    temporalis muscle;    glutamate;    pain;    neurogenic;    vasomotor;   

DOI  :  10.3390/toxins6020592

来源: mdpi

【 摘 要 】

The effect of botulinum neurotoxin type A (BoNTA) on glutamate-evoked temporalis muscle pain and vasomotor responses was investigated in healthy men and women over a 60 day time course. Subjects participated in a pre-BoNTA session where their responses to injection of glutamate (1 M, 0.2 mL) and saline (0.2 mL) into the temporalis muscles were assessed. On Day 1, BoNTA (5 U) was injected into one temporalis muscle and saline into the contralateral temporalis muscle, in a randomized order. Subjects then received intramuscular injections of glutamate (1 M, 0.2 mL) into the left and right temporalis muscles at 3 h and subsequently 7, 30 and 60 days post-injection of BoNTA. Pain intensity, pain area, and neurogenic inflammation (skin temperature and skin blood perfusion) were recorded. Prior to BoNTA treatment, glutamate evoked significantly greater pain and vasomotor reactions (P < 0.001) than saline. BoNTA significantly reduced glutamate-evoked pain intensity (P < 0.05), pain area (P < 0.01), skin blood perfusion (P < 0.05), and skin temperature (P < 0.001). The inhibitory effect of BoNTA was present at 3 h after injection, peaked after 7 days and returned to baseline by 60 days. Findings from the present study demonstrated a rapid action of BoNTA on glutamate-evoked pain and neurogenic inflammation, which is in line with animal studies.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.