scholarly journals Bladder sensation evaluation of a carrageenan-induced chronic prostatitis model using a direct measurement of the bladder mechanosensitive single-unit afferent nerve activity

2020 ◽  
Vol 93 (0) ◽  
pp. 2-LBS-23
Author(s):  
Naoki Aizawa ◽  
Tomoe Fujita
Keyword(s):  
Direct Measurement ◽  
Chronic Prostatitis ◽  
Single Unit ◽  
Afferent Nerve ◽  
Nerve Activity ◽  
Bladder Sensation

Attenuated response of renal mechanoreceptors to volume expansion in chronically hypoxic rats

1997 ◽  
Vol 273 (5) ◽  
pp. F712-F717 ◽  
Author(s):  
Chiang-Ting Chien ◽  
Tsu-Ching Fu ◽  
Ming-Shiou Wu ◽  
Chau-Fong Chen
Keyword(s):  
Volume Expansion ◽  
Single Unit ◽  
Chronic Hypoxia ◽  
Venous Pressure ◽  
Afferent Nerve ◽  
Sensory Receptors ◽  
Nerve Activity ◽  
Specific Stimulus ◽  
Single Unit Recordings ◽  
Stimulation Of

Multifiber renal afferent nerve activity responds to volume expansion in sea level rats but not in chronically hypoxic (high altitude) rats. We performed single-unit recordings of renal afferent nerve activity to characterize renal sensory receptors and their responses to volume expansion in these animals. Hypoxia was induced by placing Wistar rats in an altitude chamber (380 Torr, 5,500 m) for 4 wk. Spontaneously firing renal R2 chemoreceptor and arterial, ureteropelvic, and venous mechanoreceptors were identified. The basal activity of each receptor was similar among these rats. In response to specific stimulus, the increasing impulse of R2 chemoreceptor was similar between two groups of rats, but the increasing activity of each mechanoreceptor was less in hypoxic rats. When challenged with saline load, R2 chemoreceptor activity decreased, but all mechanoreceptors activated in all rats. Despite similar increases of arterial, renal ureteropelvic, and venous pressure during saline load, the increasing activity of each mechanoreceptor was significantly less in hypoxic rats. These results indicated chronic hypoxia attenuates the sensitivity of renal mechanoreceptors in response to the stimulation of saline load.

Threshold for efferent bladder nerve firing in the rat

1999 ◽  
Vol 276 (6) ◽  
pp. R1819-R1824
Author(s):  
Els van Asselt ◽  
Joost le Feber ◽  
Ron van Mastrigt
Keyword(s):  
Theoretical Model ◽  
Rise Time ◽  
Afferent Nerve ◽  
Bladder Pressure ◽  
Afferent Activity ◽  
Nerve Activity ◽  
Efferent Activity ◽  
Rat Bladder ◽  
Bladder Contraction

In this study, the mechanism involved in the initiation of voiding was investigated. Bladder pressure and bladder and urethral nerve activity were recorded in the anesthetized rat. Bladder nerve activity was resolved into afferent and efferent activity by means of a theoretical model. The beginning of an active bladder contraction was defined as the onset of bladder efferent firing at a certain time ( t 0). From t 0 onward, bladder efferent activity increased linearly during δ t seconds (rise time) to a maximum. The pressure at t 0 was 1.0 ± 0.4 kPa, the afferent nerve activity at t 0 was 2.0 ± 0.6 μV (53 ± 15% of maximum total nerve activity), and δ t was 11 ± 13 s. Between contractions the afferent activity at t 0 was never exceeded. Urethral afferent nerve activity started at bladder pressures of 2.1 ± 1.1 kPa. Therefore, we concluded that urethral afferent nerve activity does not play a role in the initiation of bladder contractions; voiding contractions presumably are initiated by bladder afferent nerve activity exceeding a certain threshold.

Reflex regulation of renal nerve activity in cardiac failure

1994 ◽  
Vol 266 (1) ◽  
pp. R27-R39 ◽  
Author(s):  
G. F. DiBona ◽  
L. L. Sawin
Keyword(s):  
Cardiac Index ◽  
Single Unit ◽  
Diastolic Pressure ◽  
Left Ventricular ◽  
Central Portion ◽  
Nerve Activity ◽  
Baroreflex Control ◽  
Afferent Limb ◽  
Pressure Threshold ◽  
Cardiopulmonary Baroreflex

Efferent renal sympathetic nerve activity (ERSNA) is increased in the rat with low-cardiac-output congestive heart failure (CHF; myocardial infarction). Arterial and cardiopulmonary baroreflex control of ERSNA in CHF and control rats was examined. Cardiac index and arterial pressure were lower and total peripheral resistance index, left ventricular end-diastolic pressure, and heart-to-body weight ratio were higher in CHF than in control rats. Increases in left ventricular end diastolic pressure produced by intravenous volume loading failed to increase cardiac index in CHF rats as it did in control rats. Single-unit analysis of aortic baroreceptor nerve activity showed that CHF rats had higher pressure threshold, lower frequency at pressure threshold, and lower gain than control rats. Arterial baroreflex control of ERSNA was attenuated; this was due to diminished gain of the afferent limb while the gain of the central portion of the reflex was normal. Single-unit analysis of vagal nerve activity showed that CHF rats had higher pressure threshold, lower frequency at saturation, and lower gain than control rats. Cardiopulmonary baroreflex control of ERSNA was attenuated; this was due to diminished gain of the afferent limb while the gain of the central portion of the reflex was normal. In the CHF rat, arterial and cardiopulmonary baroreflex control of ERSNA is markedly attenuated because of abnormalities in the periphery at the level of the aortic and cardiopulmonary receptors, respectively, and not in the central nervous system.

Age-dependent changes in afferent renal nerve activity in genetically hypertensive rats

1992 ◽  
Vol 262 (5) ◽  
pp. R834-R841 ◽  
Author(s):  
N. G. Moss ◽  
A. B. Scoltock
Keyword(s):  
Single Unit ◽  
Renal Ischemia ◽  
Renal Nerves ◽  
Hypertensive Rats ◽  
Nerve Activity ◽  
Renal Nerve ◽  
Wky Rats ◽  
Renal Nerve Activity ◽  
Single Unit Recordings ◽  
Wistar Kyoto

Multiunit and single-unit recordings of afferent renal nerve activity (ARNA) were obtained in anesthetized spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats between 35 and 150 days of age. Intrapelvic backflow of urine at 20 mmHg excited ARNA at all ages in SHR (152 +/- 18% above control) and WKY rats (262 +/- 24%). In SHR, complete renal ischemia was more excitatory in rats older than 120 days (1,233 +/- 103%, n = 8) than in younger SHR (317 +/- 28%, n = 42). Single-unit recordings showed that this was related to the appearance of R1 chemoreceptors in older SHR and coincided with a decline in the proportion of R2 chemoreceptors in the renal nerves. Other chemoreceptive responses were identified in single units that did not show complete R1 or R2 characteristics, some of which showed responses consistent with a transformation process from R2 to R1 receptor type. R1 chemoreceptors were not present in WKY rats studied up to 150 days of age and, unlike SHR, the proportion of R2 chemoreceptors did not decline with age. Accordingly, complete renal ischemia in WKY rats caused a comparable excitation in multiunit ARNA at all ages (285 +/- 33%, n = 43). Oral enalapril from weaning to 100 days of age prevented hypertension in SHR but did not impair the responsiveness of ARNA to any stimulus. In WKY rats, enalapril treatment for the same period resulted in exaggerated ARNA response to renal ischemia (1,250 +/- 377% above control).(ABSTRACT TRUNCATED AT 250 WORDS)

Sign in / Sign up

Export Citation Format

Share Document