scholarly journals Sympathetic Efferent Activity in the Viscerovascular Reflexes Induced by Urinary Bladder Distension.

1995 ◽  
Vol 45 (2) ◽  
pp. 265-277 ◽  
Author(s):  
Bidyut Kumar MEDDA ◽  
Juthika KOLEY ◽  
Biswanath KOLEY
Keyword(s):  
Urinary Bladder ◽  
Bladder Distension ◽  
Efferent Activity ◽  
Sympathetic Efferent Activity

Attenuation of the cardiac effects of cocaine by dizocilpine

1993 ◽  
Vol 264 (6) ◽  
pp. H1890-H1895
Author(s):  
G. R. Hageman ◽  
T. Simor
Keyword(s):  
Ventricular Arrhythmias ◽  
Cardiovascular Effects ◽  
Sympathetic Stimulation ◽  
Efferent Nerve ◽  
Efferent Activity ◽  
Life Threatening ◽  
Innervation Patterns ◽  
The Right ◽  
Sympathetic Efferent Activity ◽  
Cardiac Nerves

Cocaine abuse causes autonomic and cardiovascular effects that may be life threatening. Attenuation of cocaine-induced seizures has been produced by the noncompetitive antagonist of the N-methyl-D-aspartate receptor channel complex, dizocilpine. The purpose of the present study was, first, to determine effects of dizocilpine on the incidence of pacing-induced ventricular arrhythmias and, second, to evaluate the effects of dizocilpine on cocaine-induced depression of sympathetic efferent activity to the heart. Adult dogs were anesthetized and instrumented for blood pressure and an electrocardiogram. After vagotomy and thoracotomy, electrodes and strain gauges were sutured onto the right atrium and ventricle. A left thoracic sympathetic efferent nerve was isolated and stimulated for analysis of the innervation pattern. Arrhythmias were induced with programmed electrical stimulation of the heart before and during left cardiac sympathetic efferent nerve stimulation. The control incidence of induced arrhythmias was only 2%, which increased to 21% during left sympathetic stimulation. Cocaine (2 mg/kg iv) significantly increased these to 11 and 42%, respectively. Dizocilpine (0.5 mg/kg iv) reduced the incidence of induced ventricular arrhythmias to 2% with cocaine (P < 0.05) and to 19% with cocaine and left sympathetic stimulation (P < 0.01). One or two sympathetic efferent cardiac nerves were stimulated to evaluate innervation patterns. These nerves were severed and prepared for recording multifiber efferent neurograms. Nerve traffic was analyzed by counting positive spikes for 15 s. Control activities were normalized at 100%. Within 6 min, cocaine (2 mg/kg iv) reduced the sympathetic efferent activity to 83 +/- 4% of control (n = 14 nerves).(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Serotonergic and noradrenergic facilitation of the visceromotor reflex evoked by urinary bladder distension in rats with inflamed bladders

2008 ◽  
Vol 442 (3) ◽  
pp. 253-256 ◽  
Author(s):  
Alan Randich ◽  
Amber D. Shaffer ◽  
Chelsea L. Ball ◽  
Hannah Mebane
Keyword(s):  
Urinary Bladder ◽  
Bladder Distension

scholarly journals Extracellular adenosine 5’-triphosphate concentrations changes in rat spinal cord associated with the activation of urinary bladder afferents. A microdialysis study

2016 ◽  
Vol 14 (4) ◽  
pp. 541-546
Author(s):  
Jeová Nina Rocha ◽  
Keyword(s):  
Spinal Cord ◽  
Urinary Bladder ◽  
Chemical Activation ◽  
Female Rats ◽  
Microdialysis Probe ◽  
Primary Afferent ◽  
Extracellular Adenosine ◽  
Bladder Distension ◽  
Bladder Distention ◽  
Bladder Afferents

ABSTRACT Objective To determine adenosine 5’-triphosphate levels in the interstice of spinal cord L6-S1 segment, under basal conditions or during mechanical and chemical activation of urinary bladder afferents. Methods A microdialysis probe was transversally implanted in the dorsal half of spinal cord L6-S1 segment in female rats. Microdialysate was collected at 15 minutes intervals during 135 minutes, in anesthetized animals. Adenosine 5’-triphosphate concentrations were determined with a bioluminescent assay. In one group of animals (n=7) microdialysate samples were obtained with an empty bladder during a 10-minutes bladder distension to 20 or 40cmH2O with either saline, saline with acetic acid or saline with capsaicin. In another group of animals (n=6) bladder distention was performed and the microdialysis solution contained the ectonucleotidase inhibitor ARL 67156. Results Basal extracellular adenosine triphosphate levels were 110.9±35.34fmol/15 minutes, (mean±SEM, n=13), and bladder distention was associated with a significant increase in adenosine 5’-triphosphate levels which was not observed after bladder distention with saline solution containing capsaicin (10µM). Microdialysis with solution containing ARL 67156 (1mM) was associated with significantly higher extracellular adenosine 5’-triphosphate levels and no further increase in adenosine 5’-triphosphate was observed during bladder distension. Conclusion Adenosine 5’-triphosphate was present in the interstice of L6-S1 spinal cord segments, was degraded by ectonucleotidase, and its concentration increased following the activation of bladder mechanosensitive but not of the chemosensitive afferents fibers. Adenosine 5’-triphosphate may originate either from the central endings of bladder mechanosensitive primary afferent neurons, or most likely from intrinsic spinal neurons, or glial cells and its release appears to be modulated by capsaicin activated bladder primary afferent or by adenosine 5’-triphosphate itself.

Differential responses of regional sympathetic activity and blood flow to visceral afferent stimulation

2001 ◽  
Vol 280 (6) ◽  
pp. R1781-R1789 ◽  
Author(s):  
Hui-Lin Pan ◽  
Dwight D. Deal ◽  
Zemin Xu ◽  
Shao-Rui Chen
Keyword(s):  
Vascular Resistance ◽  
Cardiovascular Responses ◽  
Splanchnic Nerve ◽  
Visceral Afferents ◽  
Cardiovascular Reflexes ◽  
Efferent Activity ◽  
Blood Flows ◽  
The Right ◽  
Sympathetic Efferent Activity ◽  
Stimulation Of

The sympathetic nervous system is essential for the cardiovascular responses to stimulation of visceral afferents. It remains unclear how the reflex-evoked sympathetic output is distributed to different vascular beds to initiate the hemodynamic changes. In the present study, we examined changes in regional sympathetic nerve activity and blood flows in anesthetized cats. Cardiovascular reflexes were induced by either electrical stimulation of the right splanchnic nerve or application of 10 μg/ml of bradykinin to the gallbladder. Blood flows were measured using colored microspheres or the Transonic flow meter system. Sympathetic efferent activity was recorded from the left splanchnic, inferior cardiac, and tibial nerves. Stimulation of visceral afferents decreased significantly blood flows in the celiac (from 49 ± 4 to 25 ± 3 ml/min) and superior mesenteric (from 35 ± 4 to 23 ± 2 ml/min) arteries, and the vascular resistance in the splanchnic bed was profoundly increased. Consistently, stimulation of visceral afferents decreased tissue blood flows in the splanchnic organs. By contrast, activation of visceral afferents increased significantly blood flows in the coronary artery and portal vein but did not alter the vascular resistance of the femoral artery. Furthermore, stimulation of visceral afferents increased significantly sympathetic efferent activity in the splanchnic (182 ± 44%) but not in the inferior cardiac and tibial nerves. Therefore, this study provides substantial new evidence that stimulation of abdominal visceral afferents differentially induces sympathetic outflow to the splanchnic vascular bed.

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