scholarly journals MP08-08 NERVE TRANSFER FOR RESTORATION OF LOWER MOTOR NEURON-LESIONED BLADDER FUNCTION. PART 2: ATTENUATION OF PURINERGIC BLADDER SMOOTH MUSCLE CONTRACTIONS

2021 ◽  
Vol 206 (Supplement 3) ◽  
Author(s):  
Nagat Frara ◽  
Dania Giaddui ◽  
Alan S. Braverman ◽  
Danielle S. Porecca ◽  
Justin M. Brown ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Motor Neuron ◽  
Nerve Transfer ◽  
Muscle Contractions ◽  
Lower Motor Neuron ◽  
Bladder Function ◽  
Bladder Smooth Muscle ◽  
Smooth Muscle Contractions

scholarly journals Nerve transfer for restoration of lower motor neuron-lesioned bladder function. Part 2: Attenuation of purinergic bladder smooth muscle contractions.

2021 ◽  
Author(s):  
Nagat Frara ◽  
Dania Giaddui ◽  
Alan S Braverman ◽  
Danielle S. Porreca ◽  
Justin M Brown ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Ex Vivo ◽  
Purinergic Receptor ◽  
Muscle Contractions ◽  
Bladder Function ◽  
Detrusor Muscle ◽  
Bladder Smooth Muscle ◽  
Contractile Responses ◽  
Smooth Muscle Contractions

This study determined the effect of pelvic organ decentralization and reinnervation one year later on the contribution of muscarinic and purinergic receptors to ex-vivo, nerve-evoked, bladder smooth muscle contractions. Nineteen canines underwent decentralization by bilateral transection of all coccygeal and sacral (S) spinal roots, dorsal roots of lumbar (L)7 and hypogastric nerves. After exclusions, 8 were reinnervated 12 months post-decentralization with obturator-to-pelvic and sciatic-to-pudendal nerve transfers then euthanized 8-12 months later; four served as long-term decentralized only animals. Controls included six sham-operated and three unoperated animals. Detrusor muscle was assessed for contractile responses to potassium chloride (KCl) and electric field stimulation (EFS) before and after purinergic receptor desensitization with alpha, beta-methylene adenosine triphosphate (α,β-mATP), muscarinic receptor antagonism with atropine, or sodium channel blockade with tetrodotoxin. Atropine inhibition of EFS-induced contractions increased in decentralized and reinnervated animals compared to controls. Maximal contractile responses to α,β-mATP did not differ between groups. In strips from decentralized and reinnervated animals, the contractile response to EFS was enhanced at lower frequencies compared to normal controls. The observation of increased blockade of nerve-evoked contractions by muscarinic antagonist with no change in responsiveness to purinergic agonist suggests either decreased ATP release or increased ecto-ATPase activity in detrusor muscle as a consequence of the long-term decentralization. The reduction in the frequency required to produce maximum contraction following decentralization may be due to enhanced nerve sensitivity to EFS or a change in the effectiveness of the neurotransmission.

scholarly journals Oxidative Stress Contributes to Overactive Bladder in the Transgenic Sickle Cell Mouse

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4582-4582
Author(s):  
Fabio Henrique Silva ◽  
Celso Saragosa Ramos Filho ◽  
Fabiano Beraldi Calmasini ◽  
Eduardo Costa Alexandre ◽  
Roger Barbosa Ferreira ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Urinary Bladder ◽  
Overactive Bladder ◽  
Sickle Cell ◽  
Muscle Contractions ◽  
Bladder Function ◽  
Detrusor Smooth Muscle ◽  
Underactive Bladder ◽  
Response Curves ◽  
Smooth Muscle Contractions

Abstract Introduction: Lower urinary tract symptoms (LUTS) such as nocturia, urinary frequency, and urgency have been clinically reported in children and adults with sickle cell disease (SCD; Portocarrero et al J Urol 2012; Anele et al Neurourol Urodyn 2015), but little is known about the pathophysiology of micturition dysfunction in SCD patients. Transgenic sickle cell mice have been employed to better understand SCD pathophysiology. Recently, we reported that Berkeley SCD mice display underactive bladder and reduced detrusor smooth muscle contractions (Claudino et al Plos One, 2015). The homozygous Townes transgenic sickle cell mouse is another model for SCD, but urinary bladder dysfunction has never been studied in this model. Considering that SCD is associated with elevated ROS production, we hypothesized that increased ROS levels lead to alterations in the urinary bladder function of Townes SCD mice. Thus, the aim of this study was to evaluate the micturition and detrusor smooth muscle contractions in Townes transgenic sickle cell mice. Methods: Townes transgenic sickle cell mice and C57BL/6 mice (control) aged 3 to 4 months old were used. Cystometry was performed to evaluate the urinary function in vivo. In separate protocols, the urinary bladder was removed and placed in Krebs solution. Two longitudinal detrusor smooth muscle strips with intact urothelium were obtained from each bladder. The strips were mounted in 4-ml organ baths containing Krebs-Henseleit solution at 37°C continuously bubbled with a mixture of 95% O2 and 5% CO2 (pH 7.4). Cumulative concentration-response curves to muscarinic receptor agonist carbachol (CCh; 0.01-100 μM), chloride potassium (KCl; 1-300mM) and frequency-response curves for electrical field stimulation (EFS; 1-32Hz) were obtained in strips of detrusor smooth muscle from both control and SCD mice.mRNA expression for gp91phox and SOD-1 in bladder were also evaluated. Results: Micturition in SCD mice was irregular, and characterized by significant (P < 0.05) increases in the frequency of voiding contractions and nonvoiding contractions (n=5). Voiding pressure, basal pressure, capacity and threshold pressure were not changed in SCD mice. Carbachol (0.01 - 100 µM) induced concentration-dependent detrusor smooth muscle contractions in both control and SCD mice, but maximal contractile responses were significantly lower (P < 0.05) in SCD compared to control mice (1.40 ± 0.4 and 2.9 ± 0.2 mN/mg, respectively; n=5). Likewise, EFS-induced neurogenic detrusor contractions in SCD mice were 29% lower (P < 0.05) compared to the control (n=10). Contractile responses induced by KCl (1 - 300 mM) did not differ between control and SCD group (n=5). The mRNA expression for the NADPH subunit gp91phox in bladder was about 2-fold higher (P<0.05) in SCD mice compared to the control group, whereas no changes in the mRNA expression for SOD-1 were observed among groups (n=6). Infiltration by inflammatory cells (mononuclear cells) was seen in the submucosa and muscular area of bladder from SCD mice (n=4). Conclusion: Our study shows that the overactive bladder seen in SCD mouse is associated with upregulation of NADPH oxidase subunit gp91phox. Interestingly, in the contrast, the Berkeley SCD mouse exhibits an atonic detrusor smooth muscle and underactive bladder (Claudino et al Plos One 2015). One may speculate therefore that the overactive bladder in Townes SCD may progress to underactive bladder at latter stages. To confirm this hypothesis, we will evaluate the urinary bladder function in older SCD mice. Financial Support: FAPESP Disclosures No relevant conflicts of interest to declare.

scholarly journals Urothelium-dependent modulation of urinary bladder smooth muscle contractions by menthol

2012 ◽  
Vol 57 (6) ◽  
pp. 15-22 ◽  
Author(s):  
OM Paduraru ◽  
◽  
IB Filippov ◽  
OI Boldyriev ◽  
IA Vladymyrova ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Urinary Bladder ◽  
Muscle Contractions ◽  
Bladder Smooth Muscle ◽  
Urinary Bladder Smooth Muscle ◽  
Smooth Muscle Contractions

Evaluation of Airway Smooth Muscle Contractions in Vitro by High-Frequency Ultrasonic Imaging

CHEST Journal ◽  
1992 ◽  
Vol 102 (4) ◽  
pp. 1251-1257 ◽  
Author(s):  
Kunihiko Iizuka ◽  
Kunio Dobashi ◽  
Shinobu Houjou ◽  
Hiromi Sakai ◽  
Kouichi Itoh ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Airway Smooth Muscle ◽  
High Frequency ◽  
Ultrasonic Imaging ◽  
Muscle Contractions ◽  
Smooth Muscle Contractions
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