Sara Persyn - Academia.edu (original) (raw)

Papers by Sara Persyn

Front cover image: Created by Prof. dr. James Gillespie Record of arecaidine-induced autonomous b... more Front cover image: Created by Prof. dr. James Gillespie Record of arecaidine-induced autonomous bladder activity in an isolated guinea pig bladder. Immunohistochemistry picture of the major pelvic ganglion of the rat: sensory nerves staining for calcitonin gene-related peptide synapsing with small intensely fluorescent cells immunoreactive for the β 3-adrenoceptor. Cartoon illustrating the neural circuits in the major pelvic ganglion.

Additional file 1. Dataset Teughels et al. Peri-implantitis study.

BMC Oral Health, 2021

Background Choline-stabilized orthosilicic acid (CS-OSA) was previously found to stimulate bone c... more Background Choline-stabilized orthosilicic acid (CS-OSA) was previously found to stimulate bone collagen formation in osteopenia and to improve biomarkers of cartilage degradation in knee osteoarthritis. The aim of the present study was to investigate the effect of oral administration of CS-OSA on clinical symptoms of peri-implantitis and the associated bone loss. Methods Twenty-one patients with peri-implantitis were randomized in CS-OSA or placebo groups. After initial clinical and cone beam computed tomography (CBCT) measurements [probing pocket depth (PPD), bleeding on probing (BOP), mucosal recession (REC), distance from implant shoulder to alveolar crest (IS-AC) and distance from implant shoulder to first bone-to-implant contact (IS-BIC)], flap operations were performed at the peri-implantitis sites. All patients were instructed to use either placebo or CS-OSA capsules twice a day for 1 year. Measurements were repeated 6 and 12 months after randomization. Results The data of 1...

Neurourology and Urodynamics, 2015

Hypothesis / aims of study Bladder afferent outflow, linked to sensation, plays a critical role i... more Hypothesis / aims of study Bladder afferent outflow, linked to sensation, plays a critical role in bladder pathology: abnormal outflow results in altered sensation, leading to increased voiding frequency, urge and often incontinence. β3-adrenoceptor agonists have been suggested to be beneficial in treating these symptoms by mimicking sympathetic nerve activity and directly relaxing the detrusor (1). However, we hypothesize that the primary site of action may not be directly at the detrusor muscle. For many years, it has been suggested that the peripheral ganglia might play a modulatory role in bladder physiology (2). Therefore, in the present study, immunohistochemical techniques were employed to identify structures in the major pelvic ganglion (MPG) of the rat that might be involved in such neural circuitry. To further explore the role of the pelvic plexus in the control of bladder activity, we evaluated isovolumetric non-voiding activity (NVA) in a rat model in which the MPG’s wer...

European Urology Supplements, 2015

The actions of isoprenaline and mirabegron on intrinsic and muscarinic agonist induced activity i... more The actions of isoprenaline and mirabegron on intrinsic and muscarinic agonist induced activity in isolated whole bladder preparations from rat and guinea pig

Autonomic Neuroscience, 2016

β 3-adrenoceptor agonists influence overactive bladder in humans and animal models. However, data... more β 3-adrenoceptor agonists influence overactive bladder in humans and animal models. However, data is emerging that the mode of action of these drugs is complex. The present study explored the actions of the β 3-adrenergic agonist mirabegron and the non-selective agonist isoprenaline on the contractile systems in the rat and guinea pig bladder. Intravesical pressure was measured in isolated whole bladders from female adult animals. In both species spontaneous contractile activity was observed. The muscarinic agonist arecaidine produced complex responses consisting of an initial transient pressure rise followed by complex phasic activity. Three contractile elements were identified: intrinsic micro-contractile activity, initial transient response and steady state phasic activity. The intrinsic and steady state activity could be further divided into a baseline pressure with superimposed phasic activity. The effects of isoprenaline and mirabegron were investigated on these elements. In the rat, the micro-contractile activity could be completely inhibited by isoprenaline (full agonist). The arecaidineinduced initial and steady state baseline pressures were partially reduced, while the phasic activity was little affected. In the guinea pig, both the arecaidine-induced baseline pressure and the phasic activity were affected by isoprenaline. Mirabegron didn't produce significant inhibitory effects in any of the contractile elements in either species. These results show that complex contractile systems operate in the rat and guinea pig bladder that can be modulated by β 1 /β 2-adrenoceptor mechanisms. No evidence was obtained for any β 3-dependent regulation of contraction. These data support similar data in humans. Therefore the primary site of therapeutic action of β 3adrenergic agonists remains unknown.

Autonomic Neuroscience, 2016

The existence of a motor-sensory system contributing to bladder sensation is now becoming widely ... more The existence of a motor-sensory system contributing to bladder sensation is now becoming widely accepted. Although it is clear that the motor component of this system appears to be generated within the bladder wall, recent observations suggest that the mechanisms involved in its modulation may lie outside the wall. The present study was undertaken to gain more insights into the peripheral modulation of non-voiding activity and the role of the major pelvic ganglion. Male Sprague-Dawley rats anesthetized with urethane were used. The bladder was filled till 60% of the micturition threshold volume. The baseline pressure and the superimposed non-voiding activity were observed before and after consecutive bilateral transections of the hypogastric and pelvic nerves and bilateral ablation of the major pelvic ganglia. Hypogastric and pelvic nerve transection didn't significantly change the baseline pressure and superimposed non-voiding activity. Removal of the major pelvic ganglia resulted into an increased baseline pressure when compared with the control and increased amplitude of the non-voiding contractions when compared with both the decentralized condition (both hypogastric and pelvic nerves transected) and the control. The frequency of the non-voiding contractions wasn't affected. Non-voiding activity during the urine storage phase seems to be modulated at the level of the major pelvic ganglion. This suggests the possibility of local circuits between the bladder and the peripheral ganglia that may be responsible for an inhibitory component influencing non-voiding activity.

Autonomic Neuroscience, 2016

A growing body of work is describing the absence of a significant sympathetic innervation of the ... more A growing body of work is describing the absence of a significant sympathetic innervation of the detrusor implying little sympathetic regulation of bladder contractility. However, low doses of adrenergic agonists are capable of relaxing the bladder smooth muscle. If these effects underpin a physiological response then the cellular nature and operation of this system are currently unknown. The present immunohistochemistry study was done to explore the existence of alternative adrenergic signaling elements in the rat bladder wall. Using antibodies to tyrosine hydroxylase (TH) and vesicular mono-amine transporter (vmat), few adrenergic nerves were found in the detrusor although TH immunoreactive (IR) nerves were apparent in the bladder neck. TH-IR and vmat-IR nerves were however abundant surrounding blood vessels. A population of vmat-IR cells was found within the network of interstitial cells that surround the detrusor muscle bundles. These vmat-IR cells were not or only weakly TH-IR. This suggests that these interstitial cells have the capacity to store and release catecholamines that may involve noradrenaline. Cells expressing the β1-adrenoceptor (β1AR-IR) were also detected within the interstitial cell network. Double staining with antibodies to β1AR and vmat suggests that the majority of vmat-IR interstitial cells show β1AR-IR indicative of an autocrine signaling system. In conclusion, a population of interstitial cells has the machinery to store, release and respond to catecholamines. Thus, there might exist a non-neuronal β-adrenergic system operating in the bladder wall possibly linked to one component of motor activity, micro-contractions, a system that may be involved in mechanisms underpinning bladder sensation.

Journal of Urology, 2014

The existence of an inhibitory rectovesical reflex elicited by noxious colorectal afferent input ... more The existence of an inhibitory rectovesical reflex elicited by noxious colorectal afferent input was previously documented in an isovolumetric cystometry model with a ligated urethra. We compared the effect of noxious colorectal distension on bladder cystometry with an open and a ligated urethra. We used female Sprague Dawley® rats anesthetized with urethane. The effect of noxious (60 mm Hg) colorectal distension on intermittent and continuous cystometry with an open urethra was studied and then compared to inhibiting isovolumetric bladder contractions in the same rat after ligating the urethra. We evaluated volume, the pressure micturition threshold, the intercontraction interval, bladder contraction frequency and amplitude of micturition contractions. Noxious colorectal distension at 60 mm Hg did not significantly influence volume or the pressure micturition threshold during intermittent cystometry. It also did not influence the pressure micturition threshold, the intercontraction interval or bladder contraction frequency during continuous cystometry. After urethral ligation 60 mm Hg colorectal distension inhibited isovolumetric bladder contraction frequency in the same rat (mean ± SEM 0.363 ± 0.207 vs 0.886 ± 0.106 contractions per minute, p <0.05). This inhibition persisted a mean of 289.08 ± 91.24 seconds after deflating the rectal balloon. The inhibitory rectovesical reflex elicited by noxious colorectal distension clearly occurred in an isovolumetric bladder model with a ligated urethra but only to a negligible extent in filling related voiding contractions. Our results suggest that the inhibitory rectovesical reflex, most likely at the level of the lumbosacral spinal cord, is the result of an additive noxious urethral and colonic afferent stimulus.

Front cover image: Created by Prof. dr. James Gillespie Record of arecaidine-induced autonomous b... more Front cover image: Created by Prof. dr. James Gillespie Record of arecaidine-induced autonomous bladder activity in an isolated guinea pig bladder. Immunohistochemistry picture of the major pelvic ganglion of the rat: sensory nerves staining for calcitonin gene-related peptide synapsing with small intensely fluorescent cells immunoreactive for the β 3-adrenoceptor. Cartoon illustrating the neural circuits in the major pelvic ganglion.

Additional file 1. Dataset Teughels et al. Peri-implantitis study.

BMC Oral Health, 2021

Background Choline-stabilized orthosilicic acid (CS-OSA) was previously found to stimulate bone c... more Background Choline-stabilized orthosilicic acid (CS-OSA) was previously found to stimulate bone collagen formation in osteopenia and to improve biomarkers of cartilage degradation in knee osteoarthritis. The aim of the present study was to investigate the effect of oral administration of CS-OSA on clinical symptoms of peri-implantitis and the associated bone loss. Methods Twenty-one patients with peri-implantitis were randomized in CS-OSA or placebo groups. After initial clinical and cone beam computed tomography (CBCT) measurements [probing pocket depth (PPD), bleeding on probing (BOP), mucosal recession (REC), distance from implant shoulder to alveolar crest (IS-AC) and distance from implant shoulder to first bone-to-implant contact (IS-BIC)], flap operations were performed at the peri-implantitis sites. All patients were instructed to use either placebo or CS-OSA capsules twice a day for 1 year. Measurements were repeated 6 and 12 months after randomization. Results The data of 1...

Neurourology and Urodynamics, 2015

Hypothesis / aims of study Bladder afferent outflow, linked to sensation, plays a critical role i... more Hypothesis / aims of study Bladder afferent outflow, linked to sensation, plays a critical role in bladder pathology: abnormal outflow results in altered sensation, leading to increased voiding frequency, urge and often incontinence. β3-adrenoceptor agonists have been suggested to be beneficial in treating these symptoms by mimicking sympathetic nerve activity and directly relaxing the detrusor (1). However, we hypothesize that the primary site of action may not be directly at the detrusor muscle. For many years, it has been suggested that the peripheral ganglia might play a modulatory role in bladder physiology (2). Therefore, in the present study, immunohistochemical techniques were employed to identify structures in the major pelvic ganglion (MPG) of the rat that might be involved in such neural circuitry. To further explore the role of the pelvic plexus in the control of bladder activity, we evaluated isovolumetric non-voiding activity (NVA) in a rat model in which the MPG’s wer...

European Urology Supplements, 2015

The actions of isoprenaline and mirabegron on intrinsic and muscarinic agonist induced activity i... more The actions of isoprenaline and mirabegron on intrinsic and muscarinic agonist induced activity in isolated whole bladder preparations from rat and guinea pig

Autonomic Neuroscience, 2016

β 3-adrenoceptor agonists influence overactive bladder in humans and animal models. However, data... more β 3-adrenoceptor agonists influence overactive bladder in humans and animal models. However, data is emerging that the mode of action of these drugs is complex. The present study explored the actions of the β 3-adrenergic agonist mirabegron and the non-selective agonist isoprenaline on the contractile systems in the rat and guinea pig bladder. Intravesical pressure was measured in isolated whole bladders from female adult animals. In both species spontaneous contractile activity was observed. The muscarinic agonist arecaidine produced complex responses consisting of an initial transient pressure rise followed by complex phasic activity. Three contractile elements were identified: intrinsic micro-contractile activity, initial transient response and steady state phasic activity. The intrinsic and steady state activity could be further divided into a baseline pressure with superimposed phasic activity. The effects of isoprenaline and mirabegron were investigated on these elements. In the rat, the micro-contractile activity could be completely inhibited by isoprenaline (full agonist). The arecaidineinduced initial and steady state baseline pressures were partially reduced, while the phasic activity was little affected. In the guinea pig, both the arecaidine-induced baseline pressure and the phasic activity were affected by isoprenaline. Mirabegron didn't produce significant inhibitory effects in any of the contractile elements in either species. These results show that complex contractile systems operate in the rat and guinea pig bladder that can be modulated by β 1 /β 2-adrenoceptor mechanisms. No evidence was obtained for any β 3-dependent regulation of contraction. These data support similar data in humans. Therefore the primary site of therapeutic action of β 3adrenergic agonists remains unknown.

Autonomic Neuroscience, 2016

The existence of a motor-sensory system contributing to bladder sensation is now becoming widely ... more The existence of a motor-sensory system contributing to bladder sensation is now becoming widely accepted. Although it is clear that the motor component of this system appears to be generated within the bladder wall, recent observations suggest that the mechanisms involved in its modulation may lie outside the wall. The present study was undertaken to gain more insights into the peripheral modulation of non-voiding activity and the role of the major pelvic ganglion. Male Sprague-Dawley rats anesthetized with urethane were used. The bladder was filled till 60% of the micturition threshold volume. The baseline pressure and the superimposed non-voiding activity were observed before and after consecutive bilateral transections of the hypogastric and pelvic nerves and bilateral ablation of the major pelvic ganglia. Hypogastric and pelvic nerve transection didn't significantly change the baseline pressure and superimposed non-voiding activity. Removal of the major pelvic ganglia resulted into an increased baseline pressure when compared with the control and increased amplitude of the non-voiding contractions when compared with both the decentralized condition (both hypogastric and pelvic nerves transected) and the control. The frequency of the non-voiding contractions wasn't affected. Non-voiding activity during the urine storage phase seems to be modulated at the level of the major pelvic ganglion. This suggests the possibility of local circuits between the bladder and the peripheral ganglia that may be responsible for an inhibitory component influencing non-voiding activity.

Autonomic Neuroscience, 2016

A growing body of work is describing the absence of a significant sympathetic innervation of the ... more A growing body of work is describing the absence of a significant sympathetic innervation of the detrusor implying little sympathetic regulation of bladder contractility. However, low doses of adrenergic agonists are capable of relaxing the bladder smooth muscle. If these effects underpin a physiological response then the cellular nature and operation of this system are currently unknown. The present immunohistochemistry study was done to explore the existence of alternative adrenergic signaling elements in the rat bladder wall. Using antibodies to tyrosine hydroxylase (TH) and vesicular mono-amine transporter (vmat), few adrenergic nerves were found in the detrusor although TH immunoreactive (IR) nerves were apparent in the bladder neck. TH-IR and vmat-IR nerves were however abundant surrounding blood vessels. A population of vmat-IR cells was found within the network of interstitial cells that surround the detrusor muscle bundles. These vmat-IR cells were not or only weakly TH-IR. This suggests that these interstitial cells have the capacity to store and release catecholamines that may involve noradrenaline. Cells expressing the β1-adrenoceptor (β1AR-IR) were also detected within the interstitial cell network. Double staining with antibodies to β1AR and vmat suggests that the majority of vmat-IR interstitial cells show β1AR-IR indicative of an autocrine signaling system. In conclusion, a population of interstitial cells has the machinery to store, release and respond to catecholamines. Thus, there might exist a non-neuronal β-adrenergic system operating in the bladder wall possibly linked to one component of motor activity, micro-contractions, a system that may be involved in mechanisms underpinning bladder sensation.

Journal of Urology, 2014

The existence of an inhibitory rectovesical reflex elicited by noxious colorectal afferent input ... more The existence of an inhibitory rectovesical reflex elicited by noxious colorectal afferent input was previously documented in an isovolumetric cystometry model with a ligated urethra. We compared the effect of noxious colorectal distension on bladder cystometry with an open and a ligated urethra. We used female Sprague Dawley® rats anesthetized with urethane. The effect of noxious (60 mm Hg) colorectal distension on intermittent and continuous cystometry with an open urethra was studied and then compared to inhibiting isovolumetric bladder contractions in the same rat after ligating the urethra. We evaluated volume, the pressure micturition threshold, the intercontraction interval, bladder contraction frequency and amplitude of micturition contractions. Noxious colorectal distension at 60 mm Hg did not significantly influence volume or the pressure micturition threshold during intermittent cystometry. It also did not influence the pressure micturition threshold, the intercontraction interval or bladder contraction frequency during continuous cystometry. After urethral ligation 60 mm Hg colorectal distension inhibited isovolumetric bladder contraction frequency in the same rat (mean ± SEM 0.363 ± 0.207 vs 0.886 ± 0.106 contractions per minute, p <0.05). This inhibition persisted a mean of 289.08 ± 91.24 seconds after deflating the rectal balloon. The inhibitory rectovesical reflex elicited by noxious colorectal distension clearly occurred in an isovolumetric bladder model with a ligated urethra but only to a negligible extent in filling related voiding contractions. Our results suggest that the inhibitory rectovesical reflex, most likely at the level of the lumbosacral spinal cord, is the result of an additive noxious urethral and colonic afferent stimulus.