Are sham-operated mice a valid comparator in studies using a bladder outlet obstruction model? A pitfall reveals a meaningful insight.

Objective: To evaluate voiding behavior characteristics in intact and sham mice, and to examine whether intact mice show changes in "normal" micturition with aging.

Methods: A total of 72 8-week-old mice were divided into two groups - intact and sham - and the latter group was subjected to a sham of partial bladder outlet obstruction surgery. Urination frequency was evaluated (through metabolic cages) at 1, 2, 3, 6 and 12 months after the surgery (or at the equivalent time points for the intact mice).

Long-term administration of alpha-1 blocker can reverse the micturition pattern in a bladder outlet obstruction murine model.

Objective: To investigate the effect of chronic administration of an alpha-1 blocker on micturition patterns in long-term partial bladder outlet obstruction.

Methods: Mice were divided into three groups: a normal group, in which animals were fed a standard diet; a partial bladder outlet obstruction group, in which the proximal urethra was tied and animals were fed a standard diet; and a partial bladder outlet obstruction + naftopidil group, in which the proximal urethra was tied and animals were fed a standard diet containing naftopidil. Micturition behavior was evaluated in all groups for 6 months after partial bladder outlet obstruction surgery.

Pain phenotypes classified by machine learning using electroencephalography features.

Pain is a multidimensional experience mediated by distributed neural networks in the brain. To study this phenomenon, EEGs were collected from 20 subjects with chronic lumbar radiculopathy, 20 age and gender matched healthy subjects, and 17 subjects with chronic lumbar pain scheduled to receive an implanted spinal cord stimulator. Analysis of power spectral density, coherence, and phase-amplitude coupling using conventional statistics showed that there were no significant differences between the radiculopathy and control groups after correcting for multiple comparisons.

Bladder outlet obstruction disrupts circadian bladder function in mice.

The circadian clock programs daily rhythms and coordinates multiple behavioural processes, including micturition. Partial bladder outlet obstruction (pBOO) in mice produces hyperactive voiding. However, long-term effects of pBOO on bladder function have not been clarified.

An Electroencephalography Bioassay for Preclinical Testing of Analgesic Efficacy.

We present a multimodal method combining quantitative electroencephalography (EEG), behavior and pharmacology for pre-clinical screening of analgesic efficacy in vivo. The method consists of an objective and non-invasive approach for realtime assessment of spontaneous nociceptive states based on EEG recordings of theta power over primary somatosensory cortex in awake rats. Three drugs were chosen: (1) pregabalin, a CNS-acting calcium channel inhibitor; (2) EMA 401, a PNS-acting angiotensin II type 2 receptor inhibitor; and (3) minocycline, a CNS-acting glial inhibitor.

Decreased Monoamine Oxidase A Expression and Activity in the Bladders of Rats With Partial Outlet Obstruction.

Objective: To investigate changes in expression and activity of monoamine oxidase A (MAO-A) in rats with partial bladder outlet obstruction (pBOO). Previous studies suggested that monoamines, such as serotonin (5-hydroxytryptamine [5-HT]) and noradrenaline, are involved in bladder hyperactivity secondary to pBOO. However, little is known about the role of MAO-A, an enzyme oxidizing 5-hydroxytryptamine and noradrenalin, in the pathogenesis.

Piezo1 expression increases in rat bladder after partial bladder outlet obstruction.

Aims: For patients with benign prostatic hyperplasia (BPH), storage symptoms due to bladder dysfunction are bothersome, and that mechanism elucidation is needed. Piezo1, a mechanically activated ion channel, is believed to play a role in sensing bladder distension. To investigate the involvement of Piezo1 in bladder dysfunction, we examined the expression and distribution of Piezo1 and neurofilament (NF-L) to understand pathological alterations in rat bladders with partial bladder outlet obstruction (pBOO), an animal model of BPH.

Mast Cell Accumulation and Degranulation in Rat Bladder with Partial Outlet Obstruction.

Introduction: Benign prostatic hyperplasia causes partial bladder outlet obstruction (pBOO), and many patients with pBOO are affected by not only voiding symptoms but also storage symptoms. We previously suggested that enhancement of 5-hydroxytryptamine (5-HT)-induced bladder contraction in the pBOO bladder may be one cause of storage symptoms. However, little is known about the presence of 5-HT in rat bladders.

Increased expression of 5-HT(2A) and 5-HT(2B) receptors in detrusor muscle after partial bladder outlet obstruction in rats.

Serotonin (5-hydroxytryptamine; 5-HT)-induced bladder contraction is enhanced after partial bladder outlet obstruction (pBOO) in rats. We investigated time-dependent changes in bladder contraction and expression of 5-HT(2A) and 5-HT(2B) receptor mRNA in bladder tissue to elucidate the mechanism of this enhancement. On day 3 and 7 after pBOO, contractile responses of isolated rat bladder strips to 5-HT were increased compared with that in sham-operated rats; on day 14, the response had decreased to the same level as that in sham rat bladders.