Botulinum toxin type A selectivity for certain types of pain is associated with capsaicin-sensitive neurons

Antinociceptive properties of the aqueous and methanol extracts of the stem bark of Petersianthus macrocarpus (P. Beauv.) Liben (Lecythidaceae) in mice

“…In fact, they are highly involved in the transduction of formalin-and acetic acid-induced pain (Jurik et al, 2014;Matak et al, 2014). They are therefore, potential target of P. macrocarpus extracts.…”

Blockade of spinal glutamate recycling produces paradoxical antinociception in rats with orofacial inflammatory pain

“…It is well known that BoNT-A inhibits neurotransmitter release, including glutamate release from presynaptic terminals (Cui et al, 2004;Matak et al, 2014;McMahon et al, 1992). Therefore, we used BoNT-A to block the release of glutamate from presynaptic terminals.…”

Effects of botulinum toxin type A facial injection on monoamines and their metabolites in sensory, limbic and motor brain regions in rats

“…In addition, possible direct central actions mediated through toxin axonal transport from periphery to the spinal cord ventral horn have been reported in patients treated for spasticity [26]. In the present study we examined the effects of BTX-A on concentrations of neurotransmitters and their metabolites in brain regions involved in pain transmission and processing, as well as motor regions considering that BTX-A is reaching the facial nucleus and trigeminal nucleus caudalis via motor and sensory neurons, respectively [2,28]. Results showed that BTX-A did not cause a significant and neuronal survival [23,47].…”

“…Similarly, BTX-A peripheral injection has also raised the NA concentrations in striatum, a region implicated rather in retarded depression. Our previous experiments 9 suggested that BoNT/A enzymatic activity is not detectable in higher order brain regions projecting to trigeminal nucleus caudalis, however, it may affect pain-evoked neuronal activation in regions where its enzymatic activity is not detectable (locus coeruleus and periaqueductal gray) [28]. Similarly, BTX-A mediated up-regulation of serotonin and noradrenaline concentrations in hypothalamus and striatum probably results from indirect modulation of neural activity within distant brain regions rather than the direct BTX-A action.…”

“…1 unit (1 U) of BTX-A preparation contains 48 pg of 900 kDaBoNT/A complex. 5 U/kg dose was chosen based on previous experiments [28].…”