Changes in chemical coding of sympathetic chain ganglia (SChG) neurons supplying porcine urinary bladder after botulinum toxin (BTX) treatment

Abstract

Botulinum toxin (BTX) is a neurotoxin used in medicine as an effective drug in experimental therapy of neurogenic urinary bladder disorders. We have investigated the influence of BTX on the chemical coding of sympathetic chain ganglia (SChG) neurons supplying the porcine urinary bladder. The toxin was injected into the wall of the bladder. SChG neurons were visualized by a retrograde tracing method with fluorescent tracer fast blue (FB) and their chemical coding was investigated by double-labelling immunohistochemistry with antibodies against dopamine β-hydroxylase (DβH; a marker of noradrenergic neurons), neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), somatostatin (SOM), galanin (GAL), Leu5-enkephalin (L-ENK) and neuronal nitric oxide synthase (nNOS). In both the control (n = 5) and BTX-treated pigs (n = 5), the vast majority (91 ± 2.3 % and 89.8 ± 2.5 %, respectively) of FB-positive (FB+) nerve cells were DβH+. BTX injections caused a decrease in the number of FB+/DβH+ neurons that were immunopositive to NPY (39.5 ± 4.5 % vs 74.5 ± 11.9 %), VIP (8.9 ± 5.3 % vs 22.3 ± 8.8 %), SOM (5.8 ± 2.3 % vs 17.4 ± 3.7 %) or GAL (0.9 ± 1.2 % vs 5.4 ± 4.4 %) and a distinct increase in the number of FB+/DβH+ neurons that were immunoreactive to L-ENK (3.7 ± 2.9 % vs 1.1 % ± 0.8 %) or nNOS (7.7 ± 3.5 % vs 0.8 ± 0.6 %). Our study provides novel evidence that the therapeutic effects of BTX on the mammalian urinary bladder are partly mediated by SChG neurons.

The influence of intravesical administration of resiniferatoxin (RTX) on the chemical coding of sympathetic chain ganglia (SChG) neurons supplying the porcine urinary bladder

“…m Four fast blue-positive (FB+) neurons (blue; two long arrows, two short arrows) which were simultaneously n DβH+ (green; two long arrows, two short arrows) and o nNOS+ (red; two long arrows) or nNOS− (two short arrows). Bar in all images 50 µm ▸ discussion dealing with the contribution of SChG-UBPN to the innervation of the female porcine urinary bladder has been already presented in our previous paper (Lepiarczyk et al 2015). In both studies, we used different control groups.…”

“…In both studies, we used different control groups. In the earlier study (Lepiarczyk et al 2015), the wall of the urinary bladder of control pigs was injected (multiple injections) with aqueous saline solution using a cystoscope. In the present experiment, the intact animals were instilled with 5 % aqueous solution of ethyl alcohol.…”

“…DβH antiserum was applied in a mixture with antisera against NPY, VIP, SOM, GAL, L-ENK or nNOS, respectively. The presence of the above-mentioned active substances (NPY, VIP, SOM, GAL and L-ENK) or their markers (DβH, nNOSenzymes of the catecholamine or nitric oxide biosynthesis pathway, respectively) was earlier revealed in SChG neurons in the pig (Skobowiat et al 2011;Ragionieri et al 2013;Pidsudko 2014;Lepiarczyk et al 2015).…”

“…To avoid leakage, the needle was left in each place of FB injection for about 1 min. Three weeks later (which is an minimum time period needed for the retrograde tracer to be transported to the SChG and label UBPN; Bossowska et al 2009;Lepiarczyk et al 2015), the pigs were divided into two groups. Five pigs served as the controls, and they were treated with intravesical instillation of 5 % aqueous solution of ethyl alcohol (60 ml).…”

“…Although the sympathetic noradrenergic innervation of the urinary bladder arises from different sources (for review see : Jobling 2011;de Groat and Wickens 2013), it has already been proven that in females sympathetic chain ganglia (SChG) provide a great (or maybe the greatest) contribution to the bladder noradrenergic nerve supply (Vera and Nadelhaft 1992;Lepiarczyk et al 2015).…”