Effect of capsaicin-evoked jaw-muscle pain on intramuscular blood-flow

Unravelling the Mystery of Capsaicin: A Tool to Understand and Treat Pain

“…After capsaicin administration, subjects tolerated significantly lower pressure stimulation of the masseter, which demonstrates sensitization to mechanical stimuli after the intramuscular injection . The finding is supported by other studies Witting et al, 2000;Sluka, 2002;Arima et al, 2009). Central integration has also been shown: if intramuscular chemical stimulations are repeated, pain intensity and the referred pain area are increased, indicating temporal summation (GravenNielsen et al, 1997).…”

“…Central integration has also been shown: if intramuscular chemical stimulations are repeated, pain intensity and the referred pain area are increased, indicating temporal summation (GravenNielsen et al, 1997). Arima et al (2009) investigated the effect of capsaicinevoked masseter-muscle pain on intramuscular blood flow at rest and during contractions. Blood flow was investigated by a single-fiber laser Doppler probe inserted to the masseter muscle and on the skin before and after administration of intramuscular capsaicin and performance of isometric voluntary muscle contractions (Arima et al, 2009).…”

“…Arima et al (2009) investigated the effect of capsaicinevoked masseter-muscle pain on intramuscular blood flow at rest and during contractions. Blood flow was investigated by a single-fiber laser Doppler probe inserted to the masseter muscle and on the skin before and after administration of intramuscular capsaicin and performance of isometric voluntary muscle contractions (Arima et al, 2009). Intramuscular blood flow increased immediately after capsaicin injection but decreased rapidly (30 s) to preinjection values.…”

“…Hyperalgesia to punctuate stimuli was detectable immediately after block release, when A-fiber conduction returned to normal. Ziegler et al (1999) CAPSAICIN: TO UNDERSTAND AND TREAT PAIN objective methods such as measuring blood flow, recording electromyography, and electroencephalography (EEG), also exist (Chang et al, 2004;Arima et al, 2009). A model of deep tonic pain originating from the masseter muscle, mimicking clinical pain (such as, for example, in temporomandibular joint disease), was established by injection of 0.2 ml of a 100 g/ml capsaicin preparation into the deep mid-portion of the muscle (Arendt-Nielsen and Yarnitsky, 2009).…”

Effect of Masticatory Muscle Pain Control by Morphine

“…If capsaicin was injected in human masseter muscle, it induced powerful local hyperalgesia, referred pain and mechanical hypersensitivity. [20][21][22] In animal experiment with rat masseter muscle, capsaicin caused powerful pain reaction and long lasting mechanical hyperalgesia. [23][24][25] Chun and Ro suggested that intramuscular capsaicin in rat masseter muscle induced significant increase of trigeminal caudalis(Vc) neuron response and that the blockade of peripherally localized mGluR5 can effectively attenuate muscular hypersensitivity.…”