TY - JOUR
T1 - Development of an in vitro model to measure bioactivity of botulinum neurotoxin A in rat bladder muscle strips
AU - van Uhm, Janneke I. M.
AU - Beckers, Goedele M. A.
AU - van der Laarse, Willem J.
AU - Meuleman, Eric J. H.
AU - Geldof, Albert A.
AU - Nieuwenhuijzen, Jakko A.
PY - 2014/5/15
Y1 - 2014/5/15
N2 - Background: Botulinum toxin A (BoNT-A) is a new treatment modality in various causes of bladder dysfunction; like neurogenic detrusor overactivity and overactive bladder. The best technique of administrating BoNT-A in patients is unknown. A validated in vitro model could be used to investigate newer intravesical administration techniques of BoNT-A. In this study, we describe the development and validation of in vitro model to measure inhibitory effects of BoNT-A on bladder strip contractions. Methods. Rat bladder strips were mounted in organ baths filled with Krebs' solution. The strips were stimulated chemically (80 mM potassium chloride, 1 μM carbachol) and electrically (Electrical Field Stimulation (EFS) 100 shocks, 50 V, 20 Hz, every 3 minutes). The viability of the strips was measured by carbachol stimulation at the beginning and at the end of the experiments. The strips were incubated in various concentrations of BoNT-A (0.03, 0.2, 0.3 nM). Controls were incubated in Krebs' solution only. The inhibition of strip contraction induced by EFS was measured. These measurements were statistically analyzed with a log-logistic model representing diffusion. Results: All strips remained viable during the experiments. Inhibition of strip contraction was observed after incubation with 0.3 nM BoNT-A. The measurements fitted to a log-logistic model describing diffusion of BoNT-A in the bladder strip. The parameters of the log-logistic model representing diffusion were significant for 0.3 nM BoNT-A. Incubation with 0.2 nM BoNT-A showed insignificant results for 2 out of 3 runs. Incubation with 0.03 nM BoNT-A did not result in significant inhibition of strip contractions. Conclusions: An in vitro model was developed and validated in which the inhibitory effect of low concentrations of BoNT-A on bladder strip contractions can be measured. © 2014 van Uhm et al.; licensee BioMed Central Ltd.
AB - Background: Botulinum toxin A (BoNT-A) is a new treatment modality in various causes of bladder dysfunction; like neurogenic detrusor overactivity and overactive bladder. The best technique of administrating BoNT-A in patients is unknown. A validated in vitro model could be used to investigate newer intravesical administration techniques of BoNT-A. In this study, we describe the development and validation of in vitro model to measure inhibitory effects of BoNT-A on bladder strip contractions. Methods. Rat bladder strips were mounted in organ baths filled with Krebs' solution. The strips were stimulated chemically (80 mM potassium chloride, 1 μM carbachol) and electrically (Electrical Field Stimulation (EFS) 100 shocks, 50 V, 20 Hz, every 3 minutes). The viability of the strips was measured by carbachol stimulation at the beginning and at the end of the experiments. The strips were incubated in various concentrations of BoNT-A (0.03, 0.2, 0.3 nM). Controls were incubated in Krebs' solution only. The inhibition of strip contraction induced by EFS was measured. These measurements were statistically analyzed with a log-logistic model representing diffusion. Results: All strips remained viable during the experiments. Inhibition of strip contraction was observed after incubation with 0.3 nM BoNT-A. The measurements fitted to a log-logistic model describing diffusion of BoNT-A in the bladder strip. The parameters of the log-logistic model representing diffusion were significant for 0.3 nM BoNT-A. Incubation with 0.2 nM BoNT-A showed insignificant results for 2 out of 3 runs. Incubation with 0.03 nM BoNT-A did not result in significant inhibition of strip contractions. Conclusions: An in vitro model was developed and validated in which the inhibitory effect of low concentrations of BoNT-A on bladder strip contractions can be measured. © 2014 van Uhm et al.; licensee BioMed Central Ltd.
UR - https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84903274712&origin=inward
UR - https://www.ncbi.nlm.nih.gov/pubmed/24885301
U2 - https://doi.org/10.1186/1471-2490-14-37
DO - https://doi.org/10.1186/1471-2490-14-37
M3 - Article
C2 - 24885301
SN - 1471-2490
VL - 14
JO - BMC urology
JF - BMC urology
IS - 1
M1 - 37
ER -