"Ejaculatory disorders and alpha1-adrenoceptor antagonists therapy: clinical and experimental researches"

Efficacy of alfuzosin after shock wave lithotripsy for the treatment of ureteral calculi

PURPOSE

We evaluated the efficacy of alfuzosin for the treatment of ureteral calculi less than 10 mm in diameter after extracorporeal shock wave lithotripsy (ESWL).

MATERIALS AND METHODS

A randomized, single-blind clinical trial was performed prospectively by one physician between June 2010 and August 2011. A total of 84 patients with ureteral calculi 5 to 10 mm in diameter were divided into two groups. Alfuzosin 10 mg (once daily) and loxoprofen sodium 68.1 mg (as needed) were prescribed to group 1 (n=41), and loxoprofen sodium 68.1 mg (as needed) only was prescribed to group 2 (n=44). The drug administration began immediately after ESWL and continued until stone expulsion was confirmed up to a maximum of 42 days after the procedure.

RESULTS

Thirty-nine of 41 (95.1%) patients in group 1 and 40 of 43 (93.0%) patients in group 2 ultimately passed stones (p=0.96). The number of ESWL sessions was 1.34±0.65 and 1.41±0.85 in groups 1 and 2, respectively (p=0.33). The patients who required analgesics after ESWL were 8 (19.5%) in group 1 and 13 (30.2%) in group 2 (p=0.31). Visual analogue scale pain severity scores were 5.33±1.22 and 6.43±1.36 in groups 1 and 2, respectively (p=0.056). The time to stone expulsion in groups 1 and 2 was 9.5±4.8 days and 14.7±9.8 days, respectively (p=0.005). No significant adverse effects occurred.

CONCLUSIONS

The use of alfuzosin in combination with ESWL seems to facilitate stone passage and to reduce the time of stone expulsion but does not affect the stone-free rate.

Vas deferens smooth muscle responses to the nitric oxide-independent soluble guanylate cyclase stimulator BAY 41-2272

The nitric oxide-cGMP signaling pathway modulates the ejaculatory functions. The nitric oxide (NO)-independent soluble guanylate cyclase haem-dependent stimulator BAY 41-2272 potently relaxes different types of smooth muscles. However, no study investigated its effects in vas deferens smooth muscle. Therefore, we designed experiments to evaluate the in vitro relaxing responses of vas deferens to BAY 41-2272. The effects of prolonged oral intake with BAY 41-2272 in vas deferens contractions of rats treated chronically with the NO synthase inhibitor N(ω)-nitro-L-arginine methyl ester (L-NAME) were also investigated. BAY 41-2272 (0.001-100 μM) produced concentration-dependent relaxations in the prostatic and epididymal portions of vas deferens, an effect markedly reduced by the soluble guanylate cyclase inhibitor ODQ (100 μM). BAY 41-2272 significantly increased cGMP levels that were fully prevented by ODQ. In separate protocols, rats received L-NAME (20mg/rat/day) concomitantly with BAY 41-2272 (10mg/kg/day, 4 weeks), after which vas deferens contractions to electrical-field stimulation and noradrenaline were achieved. Electrical-field stimulation (1-32 Hz) evoked frequency-dependent contractions that were significantly enhanced in L-NAME-treated rats. Co-treatment with BAY 41-2272 fully reversed the increased contractile responses in L-NAME group. Noradrenaline (0.01-100 μM)-induced contractions were also greater in L-NAME-treated rats, and that was normalized by BAY 41-2272. In conclusion, BAY 41-2272 potently relaxes in vitro rat vas deferens smooth muscle and elevates the cGMP levels in an ODQ-sensitive manner. Moreover, prolonged oral intake with BAY 41-2272 restores the enhanced contractile vas deferens activity in rats treated with L-NAME. NO-independent soluble guanylate cyclase stimulators may be an alternative treatment for premature ejaculation.

Sperm chromosomal aneuploidy and DNA integrity of infertile men with anejaculation

PURPOSE

To explore sperm chromosomal aneuploidy, sperm membrane and DNA integrity in infertile patients with anejaculation.

METHODS

Semen samples were collected from 18 infertile men with spinal cord injury (SCI) by penile vibratory stimulation (PVS) and from 14 psychogenic anejaculation (PA) patients by percutaneous vasal sperm aspiration (PVSA). These semen samples as well as samples from 16 donors were analyzed using the hypo-osmotic swelling (HOS) test, the sperm chromatin dispersion (SCD) test and multi-color fluorescence in situ hybridization (FISH) with probes specific for chromosomes 13, 18, 21, X and Y.

RESULTS

There were significant differences in the percentages of motile sperm, normal morphologic sperm and sperm DNA fragmentation between the infertile men with SCI and the control group (P < 0.05 and P < 0.01). The sperm motility was significantly greater in the PA-PVSA group than in the SCI-PVS group (P < 0.01). The number of round cells per mL of semen obtained from the 18 SCI patients by PVS was between 1 and 8 million. The rate of sperm DNA fragmentation in the SCI-PVS group was higher than that of the PA-PVSA group (P < 0.05). The aneuploidy rates for the SCI patients were 2.4-fold higher for chromosomes 13, 18 and 21 and 2.2-fold higher for chromosomes X and Y than for patients in the control group (P < 0.0001).

CONCLUSIONS

The semen quality is poorer, sperm DNA fragmentation and sperm chromosomal aneuploidies are seen at a higher rate for SCI patients compared to healthy, fertile and normospermic men. Whether the difference in yield is due to increased scrotal temperature, genitourinary infection, or other reasons requires further study.

[From lab to clinical activity: adrenergic receptors and human uro-genital tissues]

BACKGROUND

Nowadays translational medicine is acquiring a more and more important role in connecting laboratory experimental results on human tissues to clinical findings and drug employment. We want to underline the importance of in vitro studies, which have been extensively performed on animal organs, but few studies have been performed on human tissues. Nevertheless, a more accurate result when compared to the in vivo use of drugs can be given only by testing the very same human tissues in a lab. We related clinical treatments of different pathologies with the results obtained in laboratory studying in vitro fragments of human organs extracted during surgery exposed to different mediators and drugs.

METHODS

Fragments of urethers, bladder (detrusorial muscle and bladder neck muscle fibers), corpora cavernosa, and vas deferens were extracted during demolitive surgery trying not to traumatize the tissue, in order to keep it alive and not to ruin its contractile fibers. The fragments were then put into polisaline solution and, once in the laboratory, fixed on suitable isolated organ support, fixed at one side of the thermostatic pool and on the other side connected to a digital monitoring system. The contractility was then studied after adding different mediators.

RESULTS

The urethers have shown a stronger response to NE and PGF2a, with a different contractility in their distal part due to a major concentration of alpha-receptors; the bladder neck has also shown a strong contractile response to NE and PGF2a, and is inhibited by alpha-blockers; the bladder detrusor, instead, responds to ACH (acetylcholine) and PGF2a; the vas deferens shows a different type of contractility in the prostatic part compared to the epididimary part when stimulated with noradrenaline and PGF2a; the corpora cavernosa respond to NE and PGF2a.

CONCLUSIONS

The results obtained after stimulating the fragments can explain and prove the receptorial activity of inner mediators and of commonly used drugs which have, for years, been used empirically; the simplicity and repetitivity of the method can be considered and used not only to research the physiological functioning of different organs, but also the functioning of new drugs before testing them on patients, being more reliable and accurate than tests on animal tissues. This experimental work has shown that using human tissues in testing specific mediators is the most reliable laboratory method.

Purinergic contraction of the rat vas deferens in L-NAME-induced hypertension: effect of sildenafil

Hypertension (HTN) is a risk factor for erectile dysfunction, but its effect on vas deferens (VD) contractility and the ejaculatory response has not been delineated. NG-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, was used for induction of nitric oxide (NO)-deficient HTN. Our aim was to evaluate the effects of L-NAME-induced HTN on rat VD contractility and to determine whether sildenafil affects VD contractility. A total of 36 male rats were divided into (1) control, (2) L-NAME-HTN, (3) sildenafil treated L-NAME-HTN groups. Group 2 was treated with L-NAME (40 mg kg(-1) per day) in drinking water for 4 weeks. Group 3 received sildenafil (1.5 mg kg(-1) per day, by oral gavage) concomitantly with L-NAME. The prostatic portion of the VD was subjected to electrical field stimulation (EFS, 1-20 Hz), and the P2X(1) agonist alpha,beta-methylene ATP (alpha,beta-meATP, 100 micromol L(-1)-1 micromol L(-1)) and the alpha1-adrenoceptor agonist phenylephrine (Phe, 100 micromol L(-1)-1 mmol L(-1)) were used to construct concentration-response curves. These experiments were repeated in the presence of P2X receptor antagonist, pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid (PPADS, 30 micromol L(-1)). VD contractions in response to EFS, alpha,beta-meATP and Phe were significantly enhanced by L-NAME. Sildenafil treatment in the L-NAME group improved the contractile response of VD to EFS (20 Hz). In the presence of PPADS, the enhanced contractile response of VD to EFS and alpha,beta-meATP in hypertensive rats was reversed. In the rat model of chronic NO depletion, the purinergic and adrenergic components and EFS affect VD contractility. The VD contractile response may be mediated more by the purinergic system than the adrenergic system, and sildenafil may alter the ejaculatory response in men with PE.

Tamsulosin versus terazosin for benign prostatic hyperplasia: a systematic review

The effectiveness and safety of tamsulosin and terazosin for patients with benign prostatic hyperplasia (BPH) was evaluated by literature review. PubMed, Embase, the Cochrane Library, Chinese biomedicine literature database (CBM), reference lists of reports, and reviews were searched for randomized controlled trials (RCTs), or quasi-RCTs of tamsulosin versus terazosin in BPH. Twelve studies involving 2,816 men were included. Outcomes included international prostate symptom score (IPSS), quality of life (QOL), maximum urinary flow rate (Q(max)), average urinary flow rate (Q(ave)), residual volume, prostate volume, and adverse effect (dizziness, severe hypotension, dry mouth). Relative risk was calculated for dichotomous data. Sensitivity analyses assessed the influence of baseline symptom severity. We found that tamsulosin is better than terazosin when assessed by IPSS (weighted mean difference (WMD)=-1.24 95% CI [- 1.98, -0.51], there was no significant difference between the two groups in QOL (WMD=0.04 95% CI [-0.16, 0.24]), Qmax (WMD=-0.38 95% CI [-1.18, 0.41]), Q(ave) (WMD=-0.39 95% CI [- 0.84, 0.06]), residual volume (WMD=-4.32 95% CI [-10.96, 2.33]), and prostate volume (WMD=-0.28 95% CI [- 3.37, 2.81]). Fewer patients receiving tamsulosin experienced dizziness (relative risk (RR) -0.38 95% CI [0.30, 0.48]), severe hypotension (RR=0.16 95% CI [0.04, 0.68]), and dry mouth (RR=0.14 95% CI [0.03, 0.77]), compared with patients receiving terazosin. Many of the high quality RCTs showed beneficial effects of tamsulosin in terms of improving IPSS. However, whether tamsulosin proves more efficacious than terazosin in long term therapy requires confirmation by additional large sample, high quality trials.

Human epididymal and prostatic tracts of vas deferens: Different contraction response to noradrenaline stimulation in isolated organ bath assay

In the present study epididymal and prostatic portions of human vas deferens were separately isolated and stimulated with exogenous noradrenaline to study their contractile properties. The results displayed that the epididymal tract produced a phasic-tonic response, while the prostatic strip produced only a phasic response suggesting a different functional role of each vas deferens segment. Moreover, it has been verified if alpha(1)-adrenoceptor antagonists doxazosin, alphuzosin and terazosin could differently block the noradrenaline response in each segment. Doxazosin, the most potent antagonist, displayed similar potency in epididymal and prostatic tract (pA(2)=8.51 and 8.42, respectively). Analogously, alphuzosin, although less potent than doxazosin, displayed in the same tracts a superimposed potency (pA(2)=7.25 and 7.30, respectively). In contrast with doxazosin and alphuzosin, terazosin displayed higher potency in blocking the contractile response in prostatic tract (pA(2)=7.67) than in epididymal segment (pA(2)=6.43). These results showed that alpha(1)-adrenoceptor antagonists doxazosin and alphuzosin, although with a different potency, did not discriminate between epididymal and prostatic segment while terazosin showed high potency in prostatic tract and only a moderate activity in epididymal section. Moreover, the biological model employed in our experiments could be a valid screening method to test the potential interferences of drugs indicated for bladder outlet obstruction with the peristaltic activity or the global tone of the human vas deferens.