Serial Changes in Bladder, Locomotion, and Levels of Neurotrophic Factors in Rats with Spinal Cord Contusion

Abstract

The aims of this study were to evaluate the evolution of the neurogenic bladder after spinal cord contusion and to correlate changes in bladder function with locomotor function and levels of neurotrophic factors. The MASCIS impactor was used to cause a mild contusion injury of the lower thoracic spinal cord of Sprague-Dawley rats. Rats were divided into four groups according to the length of time from injury to sacrifice, at 4, 14, 28, and 56 days after injury. Gait analysis was performed each week, and urodynamic study was performed just before sacrifice. Basso, Beattie, and Bresnahan (BBB) and coupling scores showed gradual recovery, as did the urinary voiding pattern and bladder volume; some parameters of micturition reached normal ranges. Brain-derived neurotrophic factor (BDNF) levels in the spinal cord, as detected by enzyme-linked immunosorbent assay, decreased with time, whereas neurotrophin-3 (NT-3) levels remained unchanged. The micturition pattern, bladder volume, and locomotor function continued to recover during the time of observation; BDNF levels in the spinal cord and bladder were inversely correlated with BBB scores and the restoration of bladder volume. We conclude that urodynamic changes in the bladder correlate with locomotion recovery but not with the levels of BDNF or NT-3 after modified mild contusion injury in rats.

Exercise Ameliorates Spinal Cord Injury by Changing DNA Methylation

“…Bladder function is frequently disrupted in SCI patients, and neurogenic bladder causes urinary tract infection, incontinence, urinary stones, and poor quality of life. The most frequent bladder dysfunctions observed in thoracic SCI patients are detrusor hyperreflexia and detrusor-sphincter dyssynergia [ 56 ], and thoracic spinal cord-contused rats also showed the same pattern in our previous studies [ 33 , 34 ]. Previously, forelimb exercise training was shown to reduce maximal pressure during bladder contraction using awake cystometry, and whole-body vibration was effective in minimizing incontinence [ 57 ].…”

“…Previously, forelimb exercise training was shown to reduce maximal pressure during bladder contraction using awake cystometry, and whole-body vibration was effective in minimizing incontinence [ 57 ]. In our previous study using sham-operated controls, bladder volume was 564.54 ± 134.01 mm 3 , micturition frequency was 0.60 ± 0.21/min, maximal pressure was 26.81 ± 5.81 cmH 2 O, and gross voiding pattern was normal [ 33 ]. Therefore, when compared with the values of the previous study, bladder volume, voiding frequency and maximal pressure, and detrusor hyperreflexia after SCI were not recovered in both the control and exercise groups ( Figure 8 b); therefore, we could not find any improvements in bladder dysfunction in the exercise group.…”

“…Evaluations of bladder function and urodynamic studies (UDS) were performed according to previous studies [ 25 , 33 , 34 ]. Briefly, the rats were anesthetized with isoflurane, and an incision was made to expose the bladder.…”

Therapeutic Potential of Induced Neural Stem Cells for Spinal Cord Injury

“…Measured parameters were the maximal micturition pressure (cmH 2 O) and frequency (time/min), the gross voiding patterns, and the regularity of the micturition pressure and frequency. The gross voiding patterns were described as normal, flaccid, or hyperreflexia according to the micturition frequency and the irregular micturition patterns as described previously (17).…”

Assessment of Depression in a Rodent Model of Spinal Cord Injury

“…Moreover, other molecular changes associated with depression, such as decreased brain-derived neurotrophic factor (BDNF) levels and changes in glucocorticoid expression, are also observed in spinal tissue after injury. [65][66][67][68][69][70][71][72][73] Fumagalli and colleagues 74 also reported that SCI reduced hippocampal expression of BDNF messenger RNA levels for at least 7 days after injury, and elevations in serum corticosterone levels appear within 24 h after a mid-thoracic (T9) contusion injury persisting for at least 1 month after injury. 75,76 Whereas there is evidence that BDNF and corticosterone levels are modulated by cytokines, it is also possible that changes in the levels of BDNF and corticosterone after SCI affect psychological wellbeing through processes independent of proinflammatory cytokine expression.…”