Botulinum neurotoxins (BTXs) inhibit the presynaptic release of acetylcoline causing a chemical denervation that results in sustained muscle weakness and have been used in the past 20 years to induce selective blocking of hyperactive striatal (and smooth) muscles. All the different seven serotypes of BTXs have in common the mechanism of action (block of the neuroexocytosis machinery inside the ...

Botulinum neurotoxins (BTXs) inhibit the presynaptic release of acetylcoline causing a chemical denervation that results in sustained muscle weakness and have been used in the past 20 years to induce selective blocking of hyperactive striatal (and smooth) muscles. All the different seven serotypes of BTXs have in common the mechanism of action (block of the neuroexocytosis machinery inside the ...

Batrachotoxin (BTX)-modified Na+ currents were characterized in GH3 cells with a reversed Na+ gradient under whole-cell voltage clamp conditions. BTX shifts the threshold of Na+ channel activation by approximately 40 mV in the hyperpolarizing direction and nearly eliminates the declining phase of Na+ currents at all voltages, suggesting that Na+ channel inactivation is removed. Paradoxically, t...

Background The objective of this study was to evaluate the influence of masticatory muscle injection of botulinum toxin type A (BTX-A) on the growth of the mandibular bone in vivo. Methods Eleven Sprague-Dawley rats were used, and BTX-A (n = 6) or saline (n = 5) was injected at 13 days of age. All injections were given to the right masseter muscle, and the BTX-A dose was 0.5 units. All of the...

α-Bungarotoxin (α-Btx) binds to the five agonist binding sites on the homopentameric α7-acetylcholine receptor, yet the number of bound α-Btx molecules required to prevent agonist-induced channel opening remains unknown. To determine the stoichiometry for α-Btx blockade, we generate receptors comprised of wild-type and α-Btx-resistant subunits, tag one of the subunit types with conductance muta...

AIM To test antinociceptive properties of botulinum toxin type A (BTX-A) in rats with carrageenan- and capsaicin-induced pain and inflammation. METHODS Pain was provoked with carrageenan (1%) or capsaicin (0.1%) injection into the plantar surface of the rat paw-pad. The effect of BTX-A 5 U/kg on carrageenan- and capsaicin-induced mechanical and thermal hypersensitivity, as well as the size of...

The effects of batrachotoxin (BTX) on the membrane potential and conductances of squid giant axons have been studied by means of intracellular microelectrode recording, internal perfusion, and voltage clamp techniques. BTX (550-1100 nM) caused a marked and irreversible depolarization of the nerve membrane, the membrane potential being eventually reversed in polarity by as much as 15 mv. The dep...

PURPOSE Intraprostatic injection of BTX-A has demonstrated clinical improvement in men with bladder outlet obstruction. We investigated the mechanisms of action of BTX-A on the prostate. MATERIALS AND METHODS Adult male Sprague-Dawley rats were injected with varying doses of BTX-A into the prostate and the prostates were harvested after 1 or 2 weeks. The effects of BTX-A on prostate histology...

BACKGROUND Many analgesic modalities have been employed with limited success to alleviate the pain associated with botulinum toxin type A (BTX-A) injections. Vibration is an effective method of reducing pain during facial cosmetic injections, but it has not been previously studied in the context of clinical cosmetic procedures. OBJECTIVES The authors evaluate the safety and efficacy of vibrat...

exposure to benzene-toluene-xylene mixture (BTX) and IL-10, TNF and IL-12 production by peripheral blood mononuclear cells. Methods Exposure was estimated in 54 workers from a paint company in Mexico City through BTX accumulated potential dose (BTX-APD). Two exposure groups were formed: high and low BTX-APD established with a cutoff point at ≥1.0 of BTXAPD, as a function of the geometric mean o...