Expression of parathyroid-hormone- related protein in the partially obstructed rabbit bladder.

Introduction: Parathyroid-hormone-related protein (PTHrP) is considered as an autocrine/paracrine regulator of growth and/or differentiation in normal and malignant tissues. We determined the distribution and density of the expression of PTHrP in the rabbit bladder during growth in response to partial outlet obstruction and its relation with the smooth muscle/collagen ratio.

Materials And Methods: A total of 30 male New Zealand White rabbits were studied.

The effect of chronic partial bladder outlet obstruction on corpus cavernosum smooth muscle and Rho-kinase in rabbits.

Aim: The goal of this study was to investigate the effect of different severities in bladder dysfunction on corpus cavernosum physiology, morphology and expression of Rho-kinase in rabbits.

Methods: Male New Zealand rabbits were divided into control, 2 and 8 weeks of partial bladder outlet obstruction (PBOO) groups. Isolated cavernosal strips from all groups were precontracted with phenylephrine and the relaxant responses to electrical field stimulation (EFS), ATP, acetylcholine, and sodium nitroprusside (SNP) were determined.

The effect of low-dose estrogen therapy on ovariectomized female rabbit bladder.

Objectives: To determine whether low-dose estrogen supplementation is as effective as high-dose supplementation in increasing bladder contractile function and mediating bladder hypertrophy and angiogenesis.

Methods: Sixteen New Zealand white female rabbits were separated into four groups of 4 rabbits each. Group 1 served as the control, and groups 2 to 4 underwent ovariectomy.

Free radical damage as a biomarker of bladder dysfunction after partial outlet obstruction and reversal.

Objective: To investigate the use of free-radical generation as a result of protein carbonylation and nitrotyrosination to characterize the level of bladder dysfunction after partial bladder outlet obstruction (PBOO) and reversal.

Materials And Methods: We surgically created PBOO in male New Zealand White rabbits; after 4 weeks of PBOO, one group of six rabbits was assessed, while the PBOO was relieved in two additional groups of six rabbits each that were assessed at 4 and 8 weeks after relieving the PBOO. Six sham-operated rabbits served as controls.

Changes in the smooth muscle of the corpora cavernosum related to reversal of partial bladder outlet obstruction in rabbits.

Previous studies have demonstrated that partial bladder outlet obstruction (PBOO) in the rabbit induces an increase in corpus cavernosum smooth muscle (CCSM) tone, which may make it difficult for the CCSM to relax. Thus, to determine whether the corpus cavernosum restores relaxation after reversal of PBOO, we investigated the physiologic, histologic, and cell biology in penises obtained from rabbits 4 weeks and 8 weeks after reversal of PBOO. CCSM from bladder outlet-obstructed and obstruction-reversed rabbits showed significant decreases in the contractile responses to phenylephrine.

Effects of L-arginine and L-NAME on chronic partial bladder outlet obstruction in rabbit.

Nitric oxide (NO) is synthesized from L-arginine by nitric oxide synthase (NOS). NOS can be inhibited by NG-nitro-L-arginine methyl ester (L-NAME) and stimulated by supplementing the diet with L-arginine. The aim of this study was to investigate the influence of NOS activity on the response of rabbits to chronic partial bladder outlet obstruction (PBOO).

Effect of letrozole on urinary bladder function in the female rabbit.

Objective: To investigate the effect of letrozole (a potent aromatase inhibitor that effectively inhibit the synthesis of oestrogen) on bladder contraction with changes in morphology and biochemistry.

Materials And Methods: Sixteen female New Zealand white rabbits were separated into four equal groups; groups 1-3 were given oral letrozole for 1, 2 and 3 weeks, and group 4 was given saline and served as the control group. At the end of the medication period each rabbit was anaesthetized and the bladder muscle strips were used for contractile, histological and biochemical studies.

Effect of age on the response to short-term partial bladder outlet obstruction in the rabbit.

Objective: To compare the physiological and structural changes after short-term partial bladder outlet obstruction (PBOO) in young and old rabbits, as PBOO results in marked contractile and histological alterations in the bladder.

Materials And Methods: In all, 20 young (7-8-week-old) and 20 old (2 years old) male rabbits were divided into four subgroups of five each (four obstructed and one sham control rabbit). The rabbits in the groups were evaluated after 1, 3, 7 and 14 days of PBOO, respectively.

Novel biomarkers of bladder decompensation after partial bladder obstruction.

Aims: Partial bladder outlet obstruction (PBOO) results in marked contractile, biochemical, and histological alterations in the bladder. Our aim was to determine the time course of progressive PBOO in the rabbit and to find parameters that marked the shift to decompensation.

Materials And Methods: Twenty-four rabbits were subjected to 1, 2, 4, and 8 weeks of PBOO.

Long term partial bladder outlet obstruction induced contractile dysfunction in male rabbits: a role for Rho-kinase.

Aims: In this study we examined the expression of Rho-kinase (ROK) isoforms in rabbit detrusor smooth muscle during the progression of partial bladder outlet obstruction and correlated them with the time course of obstruction.

Methods: Detrusor samples were obtained from bladders after 1, 2, 4, and 8 weeks of obstruction and also sham operated control rabbits. Contractile responses to field stimulation (FS) and also the smooth muscle (SM) to collagen ratio were determined in isolated bladder strips.

The effect of maturation and age on oestrogen-induced functional hypertrophy of the female rabbit bladder.

Objective: To evaluate the effect of maturation and ageing on oestrogen-induced functional hypertrophy of the female rabbit bladder.

Materials And Methods: Twenty female rabbits were separated into two groups of 10 each by age, young (immature) and old rabbits and each age group was subdivided into three subgroups. The rabbits in subgroup 1 were controls, subgroup 2 were ovariectomized (Ovx) and subgroup 3 were Ovx and received 17-beta oestradiol (1 mg/kg/day) by a subcutaneous slow-release tablet implant.

The effects of cyclical oestrogen on bladder and urethral structure and function.

Objective: To determine the effects of cycling oestrogen in rabbits, as oestrogen is essential for physiological maintenance and integrity of the female urogenital tract.

Materials And Methods: Changes in circulating oestrogen have marked effects on the bladder of experimental animals, with ovariectomy (Ovx) inducing smooth muscle (SM) and mucosal atrophy, increasing collagen synthesis and deposition, decreasing contractile function, mucosal and SM blood flow; oestrogen reverses these effects and increases bladder mass and SM density, primarily by stimulating angiogenesis and increasing blood flow. Twenty adult female New Zealand White rabbits were divided into five equal groups; group 1 served as the control group, and groups 2-5 had a bilateral Ovx.

Role of nitric oxide in urinary bladder function: effect of L-arginine.

Background: Evidence indicates that decreased blood flow to the bladder plays a major role in obstructive bladder dysfunction in the rabbit model of partial bladder outlet obstruction (PBOO), and that nitric oxide (NO) regulation of blood flow may be important in modulating the degree of obstructive bladder dysfunction. The specific aim of our study is to determine the effect of feeding rabbits a diet high in L-arginine on the response to PBOO.

Materials And Methods: Sixteen male NZ White rabbits were separated into 4 groups of 4 each.

Estrogen induces angiogenesis of the female rabbit bladder.

Postmenopausal bladder dysfunction has been speculated to involve decreased circulating estrogen levels. It is our hypothesis that estrogen induces bladder dysfunctions by modulating blood flow to the bladder, i.e.

Estrogen induced functional hypertrophy and increased force generation of the female rabbit bladder.

Aims: Estrogen is essential for physiological maintenance of the female urogenital tract. It is believed that alterations in female sex hormones play a major role in the etiology and response to urinary tract dysfunctions. In animal studies, ovariectomy (Ovx) results in smooth muscle (SM) weakness and atrophy whereas estrogen supplementation reverses these effects.

Protective effects of grape suspension on in vivo ischaemia/reperfusion of the rabbit bladder.

Objective: To investigate the potential protective effect of a grape suspension in a rabbit model of in vivo bilateral ischaemia/reperfusion (I/R), which is a causal factor in obstructive bladder dysfunction.

Materials And Methods: Six groups of four New Zealand White rabbits were treated by twice-daily gavage with aqueous grape suspension (groups 1-3) or sugar-water vehicle (groups 4-6) for 3 weeks. Groups 1 and 4 then received bilateral ischaemia for 2 h, and groups 2 and 5 received bilateral ischaemia for 2 h and reperfusion (recovery) for 1 week.

Effect of strip length on the contractile dysfunction of bladder smooth muscle after partial outlet obstruction.

Objectives: Partial outlet obstruction mediates decreased contractile responses and increased collagen synthesis; however, it is not known to what extent the increased collagen contributes to contractile dysfunction.

Methods: Sixteen WNZ rabbits were divided into three groups: control, 2-week obstructed, and 2-week sham. Each rabbit was anesthetized, and the bladder was excised and cut into equal width strips of 0.

Effect of partial outlet obstruction on nitrotyrosine content and distribution within the rabbit bladder.

Purpose: Evidence indicates that free radicals are etiological factors in obstructive bladder disease. However, it is not clear which species of reactive oxygen or nitrogen species mediate the damage. The current studies were designed to determine if partial outlet obstruction in rabbits results in the generation of nitrotyrosine (NT).

Effect of nitric oxide synthase inhibition on changes induced by estradiol in bladders from ovariectomized rabbits.

Purpose: Our current study was designed to determine whether estradiol-induced increases in bladder blood flow could be inhibited by N(omega)-nitro-L-arginine methyl ester (L-NAME), and thus whether nitric oxide was involved in estrogen-linked female bladder blood flow alterations.

Materials And Methods: Sixteen female New Zealand White rabbits were separated into 4 groups of 4 rabbits each. (1) Sham group received sham operation and injections of vehicle (peanut oil).

Effect of ethanol on protection of urinary bladder function by grape suspensions.

Objectives: To compare the protective effects of grape suspensions prepared in an aqueous vehicle with grape suspensions prepared in an 8% ethanol vehicle in rabbits subjected to partial outlet obstruction. The hypothesis was that the presence of ethanol would increase the absorption of the beneficial components of the grape suspensions and thus increase their protective ability. The use of ethanol in these studies was not to simulate wine.

Effect of age on rabbit bladder function and structure following partial outlet obstruction.

Purpose: We determined whether young and old rabbits respond differently to partial bladder outlet obstruction.

Materials And Methods: A total of 16 male New Zealand White rabbits were separated into 2 groups of 8 each. Group 1 consisted of young rabbits (age 7 weeks) and group 2 consisted of old rabbits (age 2 years).

Protection of urinary bladder function by grape suspension.

Urinary bladder dysfunction secondary to BPH is a major affliction of aging men. A rabbit model of partial outlet obstruction was used to evaluate the ability of a standardized grape suspension to protect the bladder against obstructive bladder dysfunction.Twenty-four New Zealand White rabbits were separated into four groups of six rabbits each.

Role of angiogenesis in bladder response to partial outlet obstruction.

Benign prostatic hyperplasia (BPH) is a disease that has its etiology in the abnormal growth of the adult human prostate gland that accompanies the aging process in men. The symptomatic presentation of this disease, however, is related largely to degenerative changes in the bladder that occur as a result of the increasing urethral resistance and partial bladder outlet obstruction (PBOO) caused by the growing prostate gland. BPH is characterized by bladder hypertrophy, significant decreases in urinary flow and compliance, presence of residual urine after voiding, voiding urgency and incontinence ().

Effects of castration on female rabbit bladder physiology and morphology.

Objectives: To determine the effect of ovariectomy on bladder blood flow and oxygen tension. Women are subject to bladder dysfunctions that occur less frequently in men. These include interstitial cystitis (syndrome of urgency, frequency, and pain on distension), incontinence, and bladder infections.