Physiology of Ejaculation: Emphasis on Serotonergic Control

Male delayed orgasm and anorgasmia: a practical guide for sexual medicine providers

Delayed orgasm (DO) is defined as increased latency of orgasm despite adequate sexual stimulation and desire. Anorgasmia (AO) is characterized as the absence of orgasm. Etiologies of DO/AO include medication-induced, psychogenic, endocrine, and genitopelvic dysesthesia. Given the multifactorial complex nature of this disorder, a thorough history and physical examination represent the most critical components of patient evaluation in the clinical setting. Treating DO/AO can be challenging due to the lack of standardized FDA-approved pharmacotherapies. There is no standardized treatment plan for DO/AO, though common treatments plans are often multidisciplinary and may include adjustment of offending medications and sex therapy. In this review, we summarize the etiology, diagnosis, and treatment of DO/AO.

Is bulbospongiosus muscle botox injection safe and effective in treating lifelong premature ejaculation? Randomized controlled study

PURPOSE

To evaluate the safety and efficacy of botulinum-A toxin injections into the bulbospongiosus muscle for cases of lifelong drug-resistant premature ejaculation (PE).

METHODS

Ninety-eight outpatients diagnosed with lifelong PE were randomly assigned to two groups: the botulinum-A toxin group comprising forty-nine patients and the placebo (saline) group also consisting of forty-nine patients. A 100 U botulinum-A toxin was diluted into 10 cc of saline, with 5 cc injected into one side of the muscle (botulinum-A toxin group) guided by ultrasound to distribute across most muscle fibers. The same technique was applied using the same volume of saline injected into the bulbospongiosus muscle. Intravaginal ejaculatory latency time (IELT), scores from the premature ejaculation profile (PEP), Premature Ejaculation Diagnostic Tool (PEDT), International Index of Erectile Function (IIEF), and recording of any complications were obtained. Follow-ups occurred at 1-, 3-, and 6-month post-procedure.

RESULTS

Cases receiving injections of botulinum-A toxin into the bulbospongiosus muscle showed notably extended intravaginal ejaculatory latency times compared to their initial performance after treatment. In addition, there were enhancements in PEP scores, and notably, no significant complications were reported. Conversely, the bilateral injection of saline into the bulbospongiosus muscle did not demonstrate any impact on ejaculation latencies.

CONCLUSION

Our study demonstrated that the injection of botulinum-A toxin into the bulbospongiosus muscle can serve as a safe and effective option for treating PE. Nonetheless, its clinical application warrants further studies involving larger sample sizes and longer follow-up periods.

Orexin receptors in paraventricular nucleus influence sexual behavior via regulating the sympathetic outflow in males

BACKGROUND

Orexins are hypothalamic neuropeptides associated with various neurophysiological activities such as sleep, arousal, and reward. However, there are few studies investigating the relationships between orexin receptors in the paraventricular nucleus and sexual behaviors.

OBJECTIVES

To explore the roles of orexin receptors in the paraventricular nucleus on sexual behaviors and uncover its potential mechanisms in males.

MATERIALS AND METHODS

Orexin A, orexin 1 receptor antagonist SB334867, and orexin 2 receptor antagonist TCS-OX2-29 were microinjected into the paraventricular nucleus to investigate the effects of orexin receptors on copulatory behavior testing of C57BL/6 mice. To explore if ejaculation could activate orexin 1 receptor-expressing neurons in the paraventricular nucleus, fluorescence immunohistochemical double staining was utilized. The levels of serum norepinephrine were measured and the lumbar sympathetic nerve activity was recorded to reflect the sympathetic nervous system activity. Moreover, the bulbospongiosus muscle-electromyogram was recorded and analyzed. To test whether perifornical/lateral hypothalamic area orexinergic neurons directly projected to the paraventricular nucleus, virus retrograde tracing technology was utilized.

RESULTS

Orexin A significantly enhanced sexual performance by shortening the intromission and ejaculation latencies, and increasing the mount and intromission frequencies, while the opposite outcomes appeared with SB334867. However, TCS-OX2-29 had no significant effects on sexual behaviors. Moreover, orexin A increased lumbar sympathetic nerve activity and the levels of serum norepinephrine, while SB334867 decreased lumbar sympathetic nerve activity and norepinephrine, which caused a significant decrease in sympathetic nervous system outflow. Meanwhile, a robust increase in the bulbospongiosus muscle-electromyogram activity was identified after microinjecting orexin A. Furthermore, cFos immunopositive cells were increased and double stained with orexin 1 receptor-expressing neurons in the mating group. Additionally, the retrograde tracing results demonstrated that orexinergic neurons in the perifornical/lateral hypothalamic area directly projected to the paraventricular nucleus.

CONCLUSIONS

Orexin 1 receptor in the paraventricular nucleus could influence the ejaculatory reflex via mediating the sympathetic nervous system activity, which might be of great importance in the treatment of premature ejaculation in the future.

Evaluation of sexual function after robot-assisted radical prostatectomy: A farewell to IIEF questionnaire

Longevity with localized prostate cancer (PCa) has been achieved, and the contribution of robot-assisted radical prostatectomy (RARP) to cancer control is evident. The next step to investigate in the treatment of localized PCa is improvement of the quality of life (QOL) after RARP. Erectile dysfunction has been considered a major surgical complication, and patient satisfaction after RARP has not improved despite the development of nerve preservation and penile rehabilitation. To comprehensively understand sexual dysfunction after RARP, we must investigate other complications with regard to sexual health, including low sexual desire, disturbed orgasmic function (i.e., anejaculation, orgasm intensity, painful orgasm, and climacturia), shortening of penile length, penile curvature (Peyronie's disease) and unique psychological alterations after the diagnosis of PCa, which are neglected side effects after prostatectomy. In this context, routine evaluation of erectile function by the International Index of Erectile Function only is not sufficient to understand patients' difficulties. A questionnaire is just one way of enabling patients to evaluate their pre- and postoperative concerns; listening to patients face-to-face is warranted to detect symptoms. Understanding the relationship between symptoms and preserved nerve localization can ultimately provide an individualized nerve-sparing procedure and improve patient satisfaction after RARP. In combination with psychological counseling, including the partner and medical treatment, such as testosterone replacement, it is time to reconsider ways to improve sexual dysfunction after RARP.

Impact of multiple sclerosis on male sexual and reproductive health

Multiple sclerosis (MS) is a chronic inflammatory and autoimmune neurodegenerative disease characterized by the destruction of myelin in the central nervous system, leading to significant health and quality of life burdens for patients. MS is most prevalent in younger individuals aged 20-40, a critical period when many patients hope to establish relationships and start families. While neurological disability, such as fatigue, sensory dysfunction, spasticity, and cognitive dysfunction, have been greatly improved with the advances in managing MS, physicians are frequently confronted with sexual and reproductive problems among younger male people with MS (PwMS). These issues mainly include erectile dysfunction, ejaculatory disorders, reduced libido, decreased sperm quality, and impaired male fertility. Despite recent studies indicating that MS negatively impacts the sexuality and fertility of male PwMS, these issues have not received sufficient attention. Genetic factors, autoimmunity, chronic inflammation, psychological factors, and the use of drugs may contribute to sexual/reproductive dysfunction in PwMS. However, like the overall understanding of MS pathophysiology, the complete mechanisms of its development remain unclear. In this study, we review the existing literature to summarize the range of sexual and reproductive issues unique to males with MS, explore potential underlying mechanisms, and aim to improve these issues in male PwMS. By shedding light on this overlooked aspect of MS, we hope to enhance the care and well-being of male PwMS facing these challenges.

Vital function of DRD4 in dapoxetine medicated premature ejaculation treatment

BACKGROUND

Recently, dapoxetine has been widely accepted to treat premature ejaculation by fast-inhibiting 5-hydroxytryptamine reuptake. However, dapoxetine is not suitable for all premature ejaculation patients in clinical treatment. We need to investigate and reveal the mechanism deeply to solve this problem.

OBJECTIVES

To investigate and reveal the function of dopamine D4 receptor in dapoxetine medicated premature ejaculation treatment.

MATERIALS AND METHODS

A rat model was used to screen rapid ejaculators. The molecular mechanisms of histone serotonylation-mediated regulation of dopamine D4 receptor were demonstrated by chromatin immunoprecipitation, DNA pull-down, mass spectrometry analysis, and coimmunoprecipitation experiments. The biological function of dopamine D4 receptor was investigated through in vivo experiments by intrathecal injection of shDRD4 to knockdown dopamine D4 receptor.

RESULTS

In this study, we found that dapoxetine increased expression of 5-hydroxytryptamine and dopamine D4 receptor. We demonstrated that dapoxetine increased levels of 5-hydroxytryptamine, which promoted histone serotonylation (H3K4me3Q5ser) and transcription factor myeloid zinc-finger 1 complex binding on the dopamine D4 receptor promoter, upregulated the expression of dopamine D4 receptor and thus delayed ejaculation.

DISCUSSION

In this study, we demonstrated that dapoxetine increased the levels of 5-hydroxytryptamine, which promoted histone serotonylation and myeloid zinc-finger 1 complex binding to the dopamine D4 receptor promoter and upregulated the expression of dopamine D4 receptor, thus delaying ejaculation.

CONCLUSION

It is a novel mechanism that dapoxetine take effect of premature ejaculation treatment through upregulating the dopamine D4 receptor, which indicated that upregulated dopamine D4 receptor would enhance the dapoxetine effect in premature ejaculation treatment. This may lead to the development of novel therapeutic interventions for premature ejaculation.

Ejaculation: the Process and Characteristics From Start to Finish

Purpose of Review

Semen analysis serves as the initial step in the evaluation of male infertility. However, given the difficulty in interpreting abnormal findings, physicians and patients often struggle with understanding the results. In this review, we aim to review the normal physiology of ejaculation and create an accessible resource for interpreting abnormal semen volume, viscosity, liquefaction, pH, appearance, and color.

Recent Findings

Emerging evidence has revealed that men with genitourinary tract infections have a greater number of seminal leukocytes, which may result in clumping of motile sperm and altered morphology. Hence, these patients may have abnormal sperm parameters secondary to their health status. Recent findings have further characterized the semen liquefaction process, suggesting that increased levels of semenogelin and decreased levels of proteases and plasminogen activators (e.g., urokinase and chymotrypsin) may be associated with the failure of semen to convert to a watery consistency.

Summary

This article creates a resource which may be referenced when abnormalities in semen analysis are encountered. We offer a comprehensive overview of normal ejaculation physiology and abnormal variants in male ejaculate volume-including aspermia, anejaculation, retrograde ejaculation, and hypo- and hyperspermia-and their potential etiologies. Additionally, we discuss several processes (infection, inflammation, and dysfunction of male sex glands) which may affect semen viscosity, liquefaction, and pH. Finally, our discussion of the potential colors of male ejaculate is meant to reduce the anxiety of both patient and provider. Through a better understanding of the process and varying characteristics of ejaculation, physicians may adequately counsel their patients on abnormal findings and concerns regarding infertility.

Spinal Transection Switches the Effect of Metabotropic Glutamate Receptor Subtype 7 from the Facilitation to Inhibition of Ejaculation

Metabotropic glutamate receptor subtype 7 (mGluR7) is a member of the group III mGluRs, which localize to presynaptic active zones of the central nervous system. We previously reported that mGluR7 knockout (KO) mice exhibit ejaculatory disorders, although they have normal sexual motivation. We hypothesized that mGluR7 regulates ejaculation by potentiating the excitability of the neural circuit in the lumbosacral spinal cord, because administration of the mGluR7-selective antagonist into that region inhibits drug-induced ejaculation. In the present study, to elucidate the mechanism of impaired ejaculation in mGluR7 KO mice, we eliminated the influence of the brain by spinal transection (spinalization). Unexpectedly, sexual responses of male mGluR7 KO mice were stronger than those of wild-type mice after spinalization. Histological examination indicated that mGluR7 controls sympathetic neurons as well as parasympathetic neurons. In view of the complexity of its synaptic regulation, mGluR7 might control ejaculation by multi-level and multi-modal mechanisms. Our study provides insight into the mechanism of ejaculation as well as a strategy for future therapies to treat ejaculatory disorders in humans.

A novel on-demand therapy for lifelong premature ejaculation using a miniature transperineal electrical stimulator-the vPatch: an as-treated analysis

BACKGROUND

While premature ejaculation (PE) is a common and disturbing sexual dysfunction in men, current available treatment modalities have limited efficacy and low treatment adherence.

AIM

To assess the feasibility, safety, and efficacy of the vPatch, a miniaturized on-demand perineal transcutaneous electrical stimulation device for treating PE.

METHODS

This prospective bicenter international first-in-human clinical study consisted of 2 arms, was sham controlled, and had a randomized double-blind design. In terms of statistical power calculation, 59 patients aged 21 to 56 years (mean ± SD, 39.8 ± 9.28) with lifelong PE were included. During the initial visit, intravaginal ejaculatory latency time (IELT) was measured over a 2-week run-in period. Eligibility was confirmed in visit 2, based on IELT values, medical and sexual history, and patients' individualized sensory and motor activation thresholds during perineal stimulation with the vPatch. Patients were randomized to the active (vPatch) and sham device groups in a 2:1 ratio, respectively. The vPatch device's safety profile was determined by comparing the incidence of treatment-emergent adverse events. During visit 3, IELTs, Clinical Global Impression of Change scores, and Premature Ejaculation Profile questionnaire outcomes were recorded. Primary end points assessed vPatch device efficacy as mean change in geometric mean IELT; each person was compared with himself, with and without the device, and the sham group was compared with the active group.

OUTCOMES

Outcomes included changes in IELT and Premature Ejaculation Profile before and after treatment, last visit Clinical Global Impression of Change scores, and vPatch safety profile.

RESULTS

Of 59 patients, 51 completed the study: 34 in the active group and 17 in the sham group. The baseline geometric mean IELT significantly increased from 67 to 123 seconds (P < .01) in the active group, as compared with an insignificant increase from 63 to 81 seconds (P = .17) in the sham group. The increase in mean IELT in the active group was significantly higher than in the sham group (56 vs 18 seconds, P = .01). IELT significantly increased by 3.1 times in the active vs sham group. The mean ratio of fold change (active:sham) was 1.4, significantly different from 1.0 (P = .02). No serious adverse events were reported.

CLINICAL IMPLICATIONS

Therapeutic use of the vPatch during coitus may become an on-demand, noninvasive, and drug-free treatment for PE.

STRENGTHS AND LIMITATIONS

To our knowledge, this is the first rigorous study investigating whether transcutaneous electrical stimulation during coitus could improve the symptoms of men with lifelong PE. The study is limited by the small number of patients, the exclusion of patients with acquired PE, the short-term follow up, and the use of a device based on a theoretic mechanism of action.

CONCLUSION

We demonstrated the possibility to treat lifelong PE by prolonging coitus on demand, using electric stimulation of ejaculation muscles with the vPatch.Clinical trial registration: NCT03942367 (ClinicalTrials.gov).

Current and emerging treatment options for premature ejaculation

Premature ejaculation (PE) is a prevalent male sexual dysfunction. Current standard treatment regimens include behavioural therapies, topical anaesthetics, dapoxetine and other selective serotonin reuptake inhibitors (SSRIs). Most of the pharmacotherapeutic options target neurotransmitters (such as serotonin and oxytocin) that have a role in the ejaculation mechanism. However, these treatments are mildly effective and only provide a temporary delay in the ejaculation latency time, and PE recurs when the treatment is stopped. Thus, a treatment for PE is urgently needed and research is ongoing to find the ideal PE therapy. The efficacy and safety of topical anaesthetics and SSRIs in delaying ejaculation have been confirmed in many well-designed controlled trials. Both preclinical and clinical studies on new-generation SSRIs are ongoing. Moreover, promising results came from clinical trials in which the efficacy of on-demand PE therapies targeting neurotransmitters other than serotonin, such as α1-adrenoceptor antagonists and oxytocin antagonists, was assessed. Surgical intervention and neuromodulation have been proposed as potential treatment options for PE; however, current PE guidelines do not recommend these treatments owing to safety concerns.

Efficacy of combination therapy with biofeedback and dapoxetine in lifelong premature ejaculation treatment: a prospective randomized study

PURPOSE

Premature ejaculation (PE) is a common sexual dysfunction that significantly affects the quality of life of the patient and their partner. We aimed to compare the efficacy and safety of the combination therapy with biofeedback-guided pelvic floor exercise therapy (BFT) and dapoxetine 30 mg.

METHODS

Sixty-five patients diagnosed with lifelong PE were included in the study. Patients were divided into three groups as BFT, dapoxetine 30 mg and a combination of BFT and dapoxetine 30 mg. The patients were compared with the intravaginal ejaculatory latency time (IELT) pre-treatment and post-treatment 1st and 3rd months.

RESULTS

The mean IELTs of the patients in Group 1 were 40 s in pre-treatment, 115 s at the end of the 4th week and 140 s at the end of the 12th week. The IELT values of the patients in Group 2 were 40 s in pre-treatment, 145 s in the 4th week and 170 s in the 12th week. The IELT values were calculated in Group 3 as 42.5 s in pre-treatment, 185 s in the 4th week and 205 s in the 12th week When the IELT was statistically compared between the groups at 1st and 3rd months, the duration in the combination group was found to increase significantly (p < 0.001).

CONCLUSION

Combination therapy with BFT and dapoxetine 30 mg in lifelong PE treatment is a good alternative with a low side effect profile and acceptable continuous efficiency.

Ejaculation preserving HoLEP/TURP for benign prostatic hyperplasia: myth or reality

Objectives:

To analyze whether technical modifications during transurethral resection of the prostate/holmium laser enucleation of the prostate results in preservation of antegrade ejaculation, at the same time providing effective relief from bladder outlet obstruction.

Materials and methods:

A total of 119 patients with benign prostatic hyperplasia were included in the study carried out at our center between March 2016 and December 2018. The patients were divided into two groups, with 56 (47.06%) patients in the ejaculation-preserving transurethral resection of the prostate group and 63 (52.94%) patients in the ejaculation-preserving holmium laser enucleation of the prostate group. The patients in the two groups were assessed with respect to age, prostate size, serum prostate-specific antigen and any comorbidity. The parameters assessed pre and postoperatively include Qmax, international prostate symptom score, peripheral vascular resistance, overall sexual satisfaction and overall ejaculation. All patients were regularly followed up during the study period and were included in the final analysis.

Results:

The mean (standard deviation) age, prostate size, serum prostate-specific antigen of patients who underwent ejaculation-preserving transurethral resection of the prostate and patients who underwent ejaculation-preserving holmium laser enucleation of the prostate was 61.67 (5.26)/61.48 (5.40) years, 59.75 (10.61) ml/74.44 (20.27) ml, 2.38 (0.77) ng/ml/2.47 (0.83) ng/ml, respectively. Postoperatively there was a statistically significant improvement in Qmax, international prostate symptom score and peripheral vascular resistance in both groups. The overall sexual satisfaction after surgery improved significantly in the ejaculation-preserving transurethral resection of the prostate group; however, it deteriorated significantly in the ejaculation-preserving holmium laser enucleation of the prostate group, which was statistically significant at 6 months. After treatment, the overall ejaculation assessed by asking question 9 of the international index of erectile function 15 questionnaire was unchanged in patients from the ejaculation-preserving transurethral resection of the prostate group and deteriorated in the ejaculation-preserving holmium laser enucleation of the prostate group and the difference between the two groups was statistically significant.

Conclusion:

An ejaculation preserving technique seems to be more feasible in small prostate glands when appreciable apical tissue is spared. However, holmium laser enucleation of the prostate is basically a size-independent procedure and enables the complete removal of the adenoma tissue like an open prostatectomy. To compromise the extent of tissue removal or candidate selection for a better ejaculation preservation outcome might damage the indigenous value of the holmium laser enucleation of the prostate. To conclude, if the preservation of sexual satisfaction and ejaculatory function is a priority, patients should be offered ejaculation-preserving transurethral resection of the prostate as the treatment of choice over ejaculation-preserving holmium laser enucleation of the prostate.

Variation in the sexual behavior and blood count parameters induced by sleep deprivation in male rats

BACKGROUND

Sleep is a fundamental biological requirement, and lack of sleep has increasingly been recognized to cause metabolic consequences and adversely affect immune function. Recent articles have pointed to how sleep and sexual functions may be interlinked, involving inflammation, vascular alterations, tissue damage, and endothelial dysfunction.

OBJECTIVES

We examined the effect of paradoxical sleep deprivation (PSD) on sexual behavior and hemogram parameters in male rats. In addition, we also explored whether 7 days of recovery sleep is sufficient to offset these detriments.

MATERIALS AND METHODS

 Male rats were given sexual experience through training. At the 5th test, the sexually vigorous males were randomly separated into 3 experimental groups: PSD (rats submitted to 96 hours of PSD, n = 6), RS (recovery sleep 7 days after PSD, n = 6), and control (n = 10). We evaluated the sexual behaviors of three groups. Blood samples were collected to analysis hemogram parameters.

RESULTS

In this study, we recognized that repeated copulatory tests can lead to changes in sexual behavior over time. We found that 96 hours of acute sleep deprivation impaired the sexual behavior of male rats. Our results demonstrated that 96 hours of PSD also increased levels of white blood cell (WBC) subpopulations, in particular neutrophils. Recovery sleep after sleep deprivation has a certain reversal effect on WBC subgroups and impairment of sexual behavior, with some signs that not all levels were back to baseline even after 7 days of recovery.

CONCLUSION

In general, we found that 96 hours of PSD impaired the sexual behavior of male rats. Our results demonstrated that PSD can cause systemic inflammation by affecting WBC subpopulations, in particular neutrophils. 7 days of recovery sleep after sleep deprivation has a certain reversal effect to these impairments. This article is protected by copyright. All rights reserved.

Involvement of Histamine H3 Receptor Agonism in Premature Ejaculation Found by Studies in Rats

Several of the drugs currently available for the treatment of premature ejaculation (PE) (e.g., local anesthetics or antidepressants) are associated with numerous safety concerns and exhibit weak efficacy. To date, no therapeutics for PE have been approved in the United States, highlighting the need to develop novel agents with sufficient efficacy and fewer side effects. In this study, we focused on the histamine H₃ receptor (H₃R) as a potential target for the treatment of PE and evaluated the effects of imetit (an H₃R/H₄R agonist), ciproxifan (an H₃R antagonist), and JNJ-7777120 (an H₄R antagonist) in vivo. Our in vivo electrophysiological experiments revealed that imetit reduced mechanical stimuli-evoked neuronal firing in anesthetized rats. This effect was inhibited by ciproxifan but not by JNJ-7777120. Subsequently, we evaluated the effect of imetit using a copulatory behavior test to assess ejaculation latency (EL) in rats. Imetit prolonged EL, although this effect was inhibited by ciproxifan. These findings indicate that H₃R stimulation suppresses mechanical stimuli-evoked neuronal firing in the spinal-penile neurotransmission system, thereby resulting in prolonged EL. To our knowledge, this is the first report to describe the relationship between H₃R and PE. Thus, H₃R agonists may represent a novel treatment option for PE.

Intricacies of retroperitoneal lymph node dissection for testis cancer

PURPOSE OF REVIEW

Retroperitoneal lymph node dissection (RPLND) and retroperitoneal tumor resection for germ cell cancer are complex operations requiring experience and expertise in surgical techniques necessary to achieve complete resection while minimizing morbidity. This article reviews the intricacies of RPLND for testis cancer.

RECENT FINDINGS

Surgical management of advanced testis cancer begins with an intimate understanding of retroperitoneal anatomy and the various techniques necessary to safely extirpate tumors. Preoperatively patients should undergo comprehensive counseling and obtain up-to-date imaging along with tumor markers to assist in surgical planning and evaluation of extraretroperitoneal (ERP) disease. Surgeons must be well versed in nerve-sparing techniques to maintain ejaculatory function. Newer techniques using a midline extraperitoneal technique minimizes morbidity and length of hospital stay. Special consideration should be given to the possibility of encountering ERP disease in advanced germ cell tumors, with management of these cases in tertiary care centers with multidisciplinary teams.

SUMMARY

The perioperative care of the testis cancer patient undergoing RPLND is complex. The goal is to achieve complete resection to render patients disease free while minimizing surgical and long-term morbidity. Advanced testis cancer patients should be managed at tertiary care facilities with surgical expertise and access to multidisciplinary care.

The upregulation of tryptophan hydroxylase-2 expression is important for premature ejaculation treatment with the selective serotonin reuptake inhibitor

BACKGROUND

Although there was some evidence to suggest that the serotonergic system in the brain played an important role in premature ejaculation (PE), tryptophan hydroxylase-2 (TPH2) is considered to be the key enzyme for the synthesis of 5-hydroxytryptamine (5-HT) and few studies have reported that brain TPH2 is involved in the regulation of ejaculation.

OBJECTIVES

This study aimed to investigate whether changes in brain TPH2 levels were associated with PE and to explore the effects of acute administration of dapoxetine on TPH2 expression in the brain of rats with rapid ejaculation.

MATERIALS AND METHODS

Based on the ejaculation frequency, the male rats were split into three groups: "rapid," "normal," and "sluggish" ejaculators. The level of 5-HT in the brain was determined by an enzyme-linked immunosorbent assay. TPH2 expression was detected by western blot analysis and immunohistochemistry.

RESULTS

The results showed that the concentration of 5-HT and the expression of TPH2 in rapid rats were the lowest, while those in sluggish rats were the highest. Correlation analysis also indicated the level of TPH2 was positively correlated with ejaculation latency (r = 0.8633, p < 0.0001) and negatively correlated with ejaculation frequency (r = -0.874, p < 0.001). In addition, dapoxetine acute administration to rapid rats resulted in upregulation of TPH2 expression in the brain.

DISCUSSION

There was an important link between the level of TPH2 and the change of ejaculation behaviors. Decreased expression of TPH2 in relevant brain regions will lead to rapid ejaculation. Moreover, the effect of dapoxetine on prolonging ejaculation may be due to the upregulation of TPH2 expression.

CONCLUSION

We found the correlation between the level of TPH2 in the brain and PE. The findings in this study will open up a novel way for future research in PE therapy.

Increased attentional network activity in premature ejaculation patients with anxiety revealed by resting-state functional magnetic resonance imaging

Psychological account hypothesizes that premature ejaculation (PE) is a learned pattern of rapid ejaculation maintained by anxiety about sexual failure, whereas neuropsychological accounts hypothesizes that PE is the result of dysfunction of central nervous system regulating ejaculatory. However, the central neural mechanism underlying PE patients with anxiety remains unclear. Resting-state functional magnetic resonance imaging (fMRI) data were collected in 20 PE (diagnoses based on PE Guidelines drafted by the International Society for Sexual Medicine [ISSM]) patients with anxiety and 25 matched healthy controls (HCs) from January 2019 to December 2020. The values of fractional amplitude of low-frequency fluctuation (fALFF) were compared between groups. Moreover, the correlations between fALFF and the severity of PE and anxiety of patients were examined. PE patients with anxiety had increased fALFF values in the right inferior frontal gyrus (opercular part) and middle frontal gyrus. In addition, significant positive correlations were found between the scores of PE diagnostic tool (PEDT) and fALFF values of the right inferior frontal gyrus (opercular part), as well as the right middle frontal gyrus. Moreover, fALFF values of the right inferior frontal gyrus (opercular part) and middle frontal gyrus were positively correlated with the scores of self-rating anxiety scale (SAS). Our results suggested that increased attentional network activity might play a critical role in the neural basis of PE patients with anxiety.

Physiological and pharmacological impact of oxytocin on epididymal propulsion during the ejaculatory process in rodents and men

During the emission phase of ejaculation, the sperm is driven from the cauda epididymidis, where it is stored, through the vas deferens by strong contractions. These contractions are thought of as being mainly induced by the sympathetic nervous system and the neurotransmitter noradrenaline. In the present study, we investigated the effect of oxytocin (suggested to exert effects during ejaculation as well) on defined segments of the rat and human epididymis using live imaging. Our results indicate that it is the very last part of the epididymis, segment 19 (S19) in rat and likewise segment 9 in human, which responds in a uniquely strong and rapid manner to oxytocin (similar to noradrenaline). Because of the complex nature of this contractile response, we developed an imaging analysis method, which allowed us to quantify multidirectional contractions and to display them using heat maps. The reaction of S19 to oxytocin was concentration-dependent and could be inhibited by pretreatment with oxytocin antagonists (atosiban and cligosiban), but not with an arginine vasopressin 1_A antagonist (SR49059). In both rat and human tissue, pretreatment with the alpha-1 adrenoreceptor antagonist tamsulosin inhibited the response to noradrenaline, whereas the effect of oxytocin was unimpaired. Our data (from men and rodents) strongly suggest that the hormone oxytocin is involved in the ejaculatory process. Thus, oxytocin-based medications might be a promising non-adrenergic treatment option for ejaculatory disorders. Additionally, we propose that S19 could be an advantageous model (detecting very low concentrations of oxytocin) to test the bioactivity of new oxytocin agonists and oxytocin antagonists.

A Study of Differences in Penile Dorsal Nerve Somatosensory Evoked Potential Testing Among Healthy Controls and Patients With Primary and Secondary Premature Ejaculation

BACKGROUND

Penile dorsal nerve somatosensory evoked potential (DNSEP) is a scientific and objective technique that provides effective and objective data to establish the diagnosis of premature ejaculation (PE).

AIM

To explore differences in DNSEP between patients with primary premature ejaculation (PPE) and those with secondary premature ejaculation (SPE), in order to investigate the clinical value of DNSEP in the diagnosis of PE.

METHODS

The participants were divided into a PPE group (34 cases), an SPE group (25 cases) and a healthy control group (18 cases). All participants underwent DNSEP testing, and the latencies and amplitudes of DNSEP were recorded.

OUTCOMES

Differences in the latencies and amplitudes of DNSEP were compared among the PPE, SPE, and healthy control groups.

RESULTS

The latencies of DNSEP in the PPE and SPE groups were shorter than those in the healthy control group, and these differences were statistically significant (P < 0.01). However, there was no statistically significant difference between the PPE and SPE groups (P > 0.05). The amplitudes of DNSEP in the PPE group were significantly higher than those in the healthy control group (P < 0.01). However, the amplitudes of DNSEP in the SPE group were significantly lower than those in the healthy control group (P < 0.05).

CLINICAL IMPLICATIONS

PPE and SPE can be differentiated based on differences in the amplitudes of DNSEP, providing an objective basis for treatments and follow-up examinations.

STRENGTHS AND LIMITATIONS

We evaluated differences in the amplitudes of DNSEP between PPE and SPE patients, which were rare in the published literature. However, specific causes of these differences are still unclear. SEP only reflects afferent pathways in the ejaculatory reflex arc, and role of the brain as a higher center should not be ignored.

CONCLUSION

Both PPE and SPE patients are characterized by an increased excitability of the penile sensory nerves. Sun Z, Liao Z, Zheng Q, et al. A Study of Differences in Penile Dorsal Nerve Somatosensory Evoked Potential Testing Among Healthy Controls and Patients With Primary and Secondary Premature Ejaculation. J Sex Med Rev 2021;18:732-736.

Characterizing the autonomic neural connections between the abdominal aortic and superior hypogastric plexuses: A multimodal neuroanatomical study

The aortic plexus serves as the primary gateway for sympathetic fibers innervating the pelvic viscera. Damage to this plexus and/or its associated branches can lead to an assortment of neurogenic complications such as bladder dysregulation or retrograde ejaculation. The neuroanatomy of this autonomic plexus has only recently been clarified in humans; as such, the precise function of its constituent fibers is still not clear. Further study into the functional neuroanatomy of the aortic plexus could help refine nerve-sparing surgical procedures that risk debilitating neurogenic complications, while also advancing understanding of peripheral sympathetic circuitry. To this end, the current study employed an in vivo electrostimulation paradigm in a porcine model, in combination with lipophilic neuronal tracing experiments in fixed, post-mortem human tissues, to further characterize the functional neuroanatomy of the aortic plexus. Electrostimulation results demonstrated that caudal lumbar splanchnic nerves provide primary control over the porcine bladder neck in comparison to other constituent fibers within the aortic plexus. Ex vivo human data revealed that the prehypogastric ganglion contains a significant number of neurons projecting to the superior hypogastric plexus, and that these neurons are arranged in a topographic manner within the ganglion. Altogether, these findings suggest that a pivotal sympathetic pathway mediating bladder neck contraction courses through the caudal lumbar splanchnic nerves, prehypogastric and inferior mesenteric ganglia and superior hypogastric plexus.

Premature ejaculation - current concepts in the management: A narrative review

Premature ejaculation (PE; early ejaculation or rapid ejaculation) is a common sexual problem affecting about 20-30% of men in the sexually active age group. PE can be of four types: Primary, secondary, natural variable, and subjective PE. Various non-pharmacological and pharmacological treatment options are available to treat PE including Dapoxetine, which is specifically developed for the treatment of PE. In this review, we discuss the pathophysiology and management aspects of PE.

Spontaneous Ejaculation: A Focused Review for the Clinicians

INTRODUCTION

The process of ejaculation has important meanings not only for its association with orgasm but also for the timing to ejaculate in the context of sexual activity. Spontaneous (involuntary) ejaculation (SE) without any sexual stimulation is a distressing symptom. Our understanding of SE is limited. Unfortunately, many physicians are not aware of these cases.

OBJECTIVES

The objective of this study is to describe the etiopathogenesis, clinical features, diagnosis, and treatment options for SE.

METHODS

We searched the literature for publications on "SE," "spontaneous emission" or "involuntary ejaculation," and factors influencing SE in the PUBMED/MEDLINE, Scopus, Cochrane Library, EMBASE, PsycINFO, ProQuest, Academic Search Complete database, Google Scholar, and CINAHL databases from inception to August 2020.

RESULTS

The literature search yielded 36 relevant publications reporting on 43 patients with SE. Attempts to explain the cause of pathologic SE have included 4 etiological groups (spinal cord lesions, psychological causes, rabies, and drug-induced). The underlying mechanisms responsible for induction of SE may include increased adrenergic activity, overactivity in dopaminergic system, decreased serotonergic activity, damage of descending inhibitory pathway, or penile hyperexcitability. SE may occur in the absence of an identifiable trigger or may be triggered by non-sexual circumstances (micturition, defecation, glans touch, anxiety, panic attack, or school examinations). Treatment options include psychoanalytic treatment, paroxetine, citalopram, sertraline, silodosin, and anxiolytics. In drug-induced SE, dose reduction and drug withdrawal with or without switching to another drug may relief SE.

CONCLUSIONS

SE is one of the least reported ejaculatory dysfunction. The key feature shared in common by these men is SE without any sexual thoughts or fantasies, may be triggered by non-sexual contexts, rarely associated with orgasm or erection. Treatment by psychoanalytic treatment and pharmacotherapy may be helpful. Further research might explore the definite underlying mechanisms. Abdel-Hamid IA, Ali OI. Spontaneous Ejaculation: A Focused Review for the Clinicians. Sex Med Rev 2021;9:406-422.

Premature ejaculation: an update on definition and pathophysiology

Premature ejaculation (PE) is the most common male sexual dysfunction, which represents a diagnostic as well as a therapeutic challenge for physicians. However, no universally accepted definition is currently available for PE. As a result, physicians continue to diagnose patients with PE according to major guidelines set by the professional societies. These guidelines either recommend the use of validated questionnaires or patient-reported outcomes. Recent efforts directed toward classifying PE may help provide a better understanding of the prevalence and risk factors of this disorder. While the exact etiology of PE has not been clearly elucidated, several risk factors have been strongly reported in the literature. Clearly, to understand the revised definition of PE, its etiology and pathophysiology is necessary to improve the clinical management of this medical condition and form the basis of future research in this regard. In this review, we highlight the past and current definitions of PE and present an appraisal on the classifications and theories suggested for the etiopathogenesis of PE.

Association between 5-hydroxytryptamine transporter gene-linked promoter region polymorphism and the susceptibility of lifelong premature ejaculation: a meta-analysis involving 1,604 subjects

The relationship between 5-hydroxytryptamine transporter-linked promoter region (5-HTTLPR) gene and lifelong premature ejaculation (LPE) risk was discussed widely for the last few years, which was still controversial and remained to be explored. We performed the meta-analysis with 8 reliable research, which were searched in the following databases: PubMed, Embase and Cochrane Library. We also performed random and fixed effects models to evaluate the odds ratios (ORs) and 95% confidence intervals respectively. By pooling all included studies, we found that SS genotype of 5-HTTLPR polymorphism was linked with significantly higher PE risk in Caucasian population (OR =0.635, 95% CI: 0.417–0.958, I²=0.311, P=0.035), and S-allele of 5-HTTLPR polymorphism increased the risk of LPE significantly in Asian population (OR =0.656, 95% CI: 0.539–0.799, I²=0.435, P<0.001). However, no significant was observed between 5-HTTLPR gene polymorphism and LPE risk in overall studies. Further studies were anticipated to be done.

Can low serum brain-derived neurotrophic factor levels be associated with lifelong premature ejaculation?; A pilot study

This study aimed to present the association between the serum level of brain-derived neurotrophic factor (BDNF) and the lifelong pre-mature ejaculation (PE). The data of 40 patients with lifelong PE and 40 healthy controls were evaluated prospectively. PE diagnostic tool and patient-reported outcome measures were performed to the participants. The serum BDNF level measurement was made after the collecting of blood samples in both groups. The mean ± SD age of the PE and control group was 34.43 ± 5.71 and 33.03 ± 3.97 years respectively (p = .228). Only the participant who has been married included in the study, and there was no difference in the mean marriage duration. In both groups, smoking status, alcohol use and body mass index were similar. The median PE diagnostic tool scores were 15 (11-20), and serum BDNF levels were 225.3 (26.1-689.6) ng/ml in the PE group, 5 (0-9) and 540.9 (102.9-769.2) ng/ml in the control group respectively (p < .001 for both). The patients with PE had significantly lower serum BDNF levels. Our study suggests that lower serum BDNF levels may be directly related to lifelong PE.

Premature ejaculation in patients with lower urinary tract symptoms: a systematic review

Lower urinary tract symptoms (LUTS) refer to a group of symptoms related to bladder, prostate, and urethra. LUTS are common in men and the severity increases with age. LUTS are frequently associated with sexual dysfunction, such as premature ejaculation (PE), standing as the most common sexual dysfunction in men. Both LUTS and PE cause distress and dissatisfaction for the patient and his partner. This systematic review aims to determine the relationship between LUTS and PE in men. Two reviewers independently conduct a literature search in five online databases (PubMed, Scopus, Proquest, ClinicalKey, and ScienceDirect). In addition, reviewers also reviewed the reference list of chosen articles to identify additional relevant studies. Twelve articles were included in this systematic review that consists of one cohort study and 11 cross-sectional studies. The total scores of each identified study ranged from "poor" to "good." The prevalence of PE in LUTS ranged from 12 to 77%. Most of the studies showed a significant relationship between LUTS and PE. PE is more common in older age with the peak prevalence in age of 60-69 years old. There is a possible association between PE and LUTS. Further research using cohort or case-control study design on this topic is needed.

Lorcaserin Administration has Pro-Ejaculatory Effects in Rats via 5-HT2C Receptors Activation: A Putative Pharmacologic Strategy to Delayed Ejaculation?

BACKGROUND

Lorcaserin is an anti-obesity drug whose weight loss effect results from 5-hydroxytryptamin (5-HT)_2C receptors activation. The 5-HT_2C receptor was shown to participate in the physiological control of ejaculation, but no data addressing a putative effect of lorcaserin on ejaculation exist.

AIM

To investigate the effects of lorcaserin in different in vitro and in vivo experimental models of ejaculation in rats.

METHODS

Contractile responses to lorcaserin in rat seminal emission organs in vitro (prostatic and epididymal vas deferens, cauda epididymis, and seminal vesicles), analysis of male rat copulatory behavior, and electromyographic recording of bulbospongiosus muscle in anesthetized animals were studied.

MAIN OUTCOME MEASURES

The main outcome measures included in vitro contraction of seminal emission organs and evaluation of the male rat copulatory behavior. The male rat sexual behavior in terms of copulation latency, ejaculation latency, mount and intromission frequency, and ejaculation frequency of sexually experienced adult male rats with a receptive female were also recorded.

RESULTS

Lorcaserin (1.0 nM to 1.0 mM) had no significant effects on the in vitro contractility of seminal emission organs smooth muscle (cauda epididymis, vas deferens, and seminal vesicles). On the other hand, lorcaserin administration (0.3-1.0 mg/kg, intravenous) induced ejaculation in anesthetized rats, which was prevented by the 5-HT_2C-selective antagonist SB 242084 (0.1 and 0.3 mg/kg, intravenous). Single-dose treatment of non-anesthetized male rats with lorcaserin (1.0, 4.0, or 10 mg/kg, per os) induced non-copulating ejaculations in sexually naïve rats. Lorcaserin also had pro-ejaculation effects by decreasing the ejaculation threshold of copulating rats by half. The pro-ejaculatory effects of lorcaserin were reversible as the ejaculation threshold of treated rats recovered after a 1-week washout period.

CLINICAL IMPLICATIONS

Due to its reported clinical safety, repurposing lorcaserin for the treatment of delayed ejaculation may be suggested.

STRENGTHS & LIMITATIONS

The pro-ejaculatory effect of lorcaserin administration and the role of 5-HT_2C were demonstrated in different experimental models of ejaculation in rats. The lack of studies in putative experimental models of delayed ejaculation is a limitation of this study.

CONCLUSION

Our results demonstrate that the clinically approved 5-HT_2C agonist lorcaserin is a strong facilitator of ejaculation in rats. de Almeida Kiguti LR, Pacheco TL, Antunes E, et al. Lorcaserin Administration has Pro-Ejaculatory Effects in Rats via 5-HT2C Receptors Activation: A Putative Pharmacologic Strategy to Delayed Ejaculation? J Sex Med 2020;17:1060-1071.

Transcutaneous functional electrical stimulation-a novel therapy for premature ejaculation: results of a proof of concept study

Premature Ejaculation (PE) is a very common and disturbing sexual dysfunction in men. Currently available treatment modalities are associated with limited efficacy and low treatment adherence. In this prospective, single-blinded, self-controlled study, we evaluated the efficacy and safety of transcutaneous electrical stimulation (TES) for the treatment of (PE). We included 23 patients aged 20-60 (mean: 38.7) with lifelong PE. On the first visit, we delivered either TES or sham treatment to the perineum, based on the enrollment order. For stimulation, we used a commercial neuromuscular electrical stimulation device. The patients were invited for the second visit after at least 7 days for receiving the alternating treatment. During the treatment sessions, the patients were left alone in a privet silent room to masturbate and a stopwatch was used to measure their masturbation ejaculatory latency time (MELT). The patients also filled-out safety questionnaires after each visit and on each of the 3 following days. Of the 20 patients who completed the study, 17 (85%) experienced prolonged MELT under TES compared with the sham treatment. Mean MELT values increased 3.5-folds under TES (p = 0.0009). We demonstrated a significant increase in MELT in lifelong PE patients using TES. This therapeutic option may have the potential to become an on-demand treatment option for PE. Future studies with wireless devices are needed to confirm the efficacy and safety of this treatment concept during intercourse.

Central pattern generators in the brainstem and spinal cord: an overview of basic principles, similarities and differences

Central pattern generators (CPGs) are generally defined as networks of neurons capable of enabling the production of central commands, specifically controlling stereotyped, rhythmic motor behaviors. Several CPGs localized in brainstem and spinal cord areas have been shown to underlie the expression of complex behaviors such as deglutition, mastication, respiration, defecation, micturition, ejaculation, and locomotion. Their pivotal roles have clearly been demonstrated although their organization and cellular properties remain incompletely characterized. In recent years, insightful findings about CPGs have been made mainly because (1) several complementary animal models were developed; (2) these models enabled a wide variety of techniques to be used and, hence, a plethora of characteristics to be discovered; and (3) organizations, functions, and cell properties across all models and species studied thus far were generally found to be well-preserved phylogenetically. This article aims at providing an overview for non-experts of the most important findings made on CPGs in in vivo animal models, in vitro preparations from invertebrate and vertebrate species as well as in primates. Data about CPG functions, adaptation, organization, and cellular properties will be summarized with a special attention paid to the network for locomotion given its advanced level of characterization compared with some of the other CPGs. Similarities and differences between these networks will also be highlighted.

Piper auritum Kunth (Piperaceae) improves the sexual performance of sluggish male rats through enhancing ejaculation

ETHNOPHARMACOLOGICAL RELEVANCE

Piper auritum Kunth is employed as an aphrodisiac in the traditional medicine, but corroborative evidence for such effect is scarce.

AIM OF THE STUDY

The pro-sexual effect of an aqueous extract of P. auritum and its possible mechanisms were analyzed in two paradigms of male sexual function.

MATERIAL AND METHODS

Effects of an aqueous extract of P. auritum (PA, single administration) were investigated in the fictive ejaculation, and copulatory behavior paradigms in sexually sluggish male rats. WAY 100635 (antagonist of 5-HT_1A receptors), atosiban (antagonist of oxytocinergic receptors), L-NAME (inhibitor of the nitric oxide synthase) and baclofen (antagonist of GABA_B receptors) were used as pre-treatments in order to investigate the role of different neurotransmitter systems in PA actions. Chemical profile of PA was determined by Gases Chromatography and Ultra Performance Chromatography-Electrospray Ionization-Masses Spectrometry (UPLC-ESI-MS).

RESULTS

In males with retarded ejaculation, PA stimulated ejaculatory behavior and recovered electromyographic activity of pelvic musculature participating in seminal emission and ejaculation. All pre-treatments blocked stimulating effects of PA on the fictive ejaculation; additionally WAY 100635 interfered with PA actions on ejaculatory behavior. Safrol, apigenin dimethylether, myristicin, vaccihein A, sakuranin and sakuranetin flavonoids, were main constituents of PA, with possible participation in its pro-sexual effects.

CONCLUSIONS

Pro-sexual effects of P. auritum elicited at level of ejaculation were mediated by several neurotransmitter systems, among which serotonin and its 5-HT_1A receptors play an important role. Present findings support P. auritum reputation as an aphrodisiac, with potential use in delayed ejaculation disorder.

Contractile Effects of Serotonin (5-HT) in the Rat Cauda Epididymis: Expression and Functional Characterization of 5-HT Receptors

Serotonin [5-hydroxytryptamine (5-HT)] exerts multiple central and peripheral functions. High concentrations of 5-HT have been found in the epididymis, a ductal organ that plays pivotal roles in sperm transport and maturation. The contraction of the epididymal smooth muscle is essential for sperm transport and emission during ejaculation. The contributions of the epididymal 5-HT system to these events are poorly understood. Here, we assessed the contractile function of 5-HT in the rat cauda epididymis (CE), pharmacologically targeting the receptor(s) and the reuptake mechanism involved in this system. Segments of CE duct from adult Wistar rats were set up in an organ bath system for isometric tension recordings, and concentration-response curves to 5-HT and norepinephrine were obtained. 5-HT elicited concentration-dependent contractions of the CE duct (pEC₅₀ = 6.5 ± 0.1) that were potentiated with high potency by the norepinephrine transporter (NET) inhibitor desipramine and with low potency by the highly selective serotonin transporter inhibitor paroxetine, indicating that the NET is the major mediator of 5-HT reuptake in vitro. CE contractions to 5-HT were antagonized by the α ₁-adrenoceptor (α ₁-AR) antagonist prazosin (pA ₂ ≅ 8.9), 5-HT_2A/2C antagonists ketanserin (pA ₂ ≅ 9.4) and fluoxetine (pA ₂ ≅ 7.4), and 5-HT_1A ligands WAY 100635 (pA ₂ ≅ 8.9) and buspirone (pA ₂ ≅ 7.3). Reverse transcriptase polymerase chain reaction analysis demonstrated that 5-HT_1A and 5-HT_2A transcripts are highly abundant in the cauda epididymis, whereas 5-HT_2C transcript was not found. Altogether, our results reveal that contractions of the CE duct to 5-HT encompasses at least activation of α ₁-ARs and 5-HT_1A and 5-HT_2A receptors, providing new insights into the roles of 5-HT on the epididymal function.

Serum vitamin D level may be a novel potential risk factor for premature ejaculation: a comparative study

PURPOSE

To compare serum level of vitamin D [25(OH)D] in patients with life-long premature ejaculation (LPE) versus healthy controls.

METHODS

Healthy married potent males were recruited from February 2017 to January 2018. Group A included 40 patients suffering from LPE who were compared versus 40 healthy controls (Group B). Participants suffering from hormonal disorders, obesity, neurological, psychological, or chronic diseases or taking medications that may affect ejaculatory function, serum level of vitamin D, or the accuracy of intra-vaginal ejaculation latency time (IELT) were excluded. LPE was self-reported by the patients with subsequent feelings of frustration and measured by premature ejaculation diagnostic tool (PEDT) and IELT using stopwatch handled by their partners. 25(OH)D was measured by obtaining 2 ml of venous blood. Statistical analysis was performed using Student t, Mann-Whitney, Chi square tests, logistic regression analysis, and Spearman correlation.

RESULTS

Sixteen (20%) participants had vitamin D insufficiency/deficiency. All of them were in PE group. 25(OH)D correlated significantly with IELT (r² = 0.349; p < 0.001) and PEDT (r² = 0.425; p < 0.001). There was no statistically significant difference in age (p = 0.341), BMI (p = 1) or IIEF-5 (p = 0.408) in both groups. 25(OH)D was significantly lower in patients than controls (35.75 vs. 58.92 ng/ml, p < 0.001). ROC analysis revealed that the best cut-off value of 25(OH)D to detect patients suffering from LPE was 50.65 ng/ml with a sensitivity and specificity of 85% for both. 25(OH)D remained a significant risk factor for LPE in the logistic regression analysis (p < 0.001).

CONCLUSIONS

The current study showed that vitamin D has significant association with LPE and correlates significantly with IELT and PEDT.

Contemporary management of ejaculatory dysfunction

Although erectile dysfunction is the most common disorder of male sexual health, ejaculatory dysfunction is the most common form of sexual dysfunction experienced by men. Ejaculatory dysfunction covers a broad range of disorders that we have divided into four main categories: premature ejaculation, delayed ejaculation (DE)/anorgasmia, unsatisfactory sensation of ejaculation (including painful ejaculation and ejaculatory anhedonia), and absent ejaculate (including retrograde ejaculation and aspermia). We also cover several special scenarios including hematospermia, spinal cord injury and fertility with anejaculation. In this paper, we will review the anatomy and pathophysiology of normal ejaculation to establish the baseline knowledge of how this pathway can go awry. We will then briefly review the critical diagnostic criteria, pertinent steps in evaluation, risk factors, and causes (if known) for each of the ejaculatory disorders. Finally, the bulk of the paper will discuss current management strategies of each disorder.

Evaluation of the Spermatogenic Activity of Polyherbal Formulation in Oligospermic Males

The therapeutic use of natural herbs is an ancient human civilization act and the numbers of people have reliance on their pharmacological properties and preferred to use the natural herbs. People also use to consume these herbs as supplements to energize, bolster, and eventually enhance sexual ability. Polyherbal formulation (PHF) is one of these herbal amalgams that can be used to treat sexual dysfunction including erectile dysfunction, impotence, ejaculation dysfunction, and hypogonadism. The pilot study was aimed at evaluating the capacity of PHF in enhancing the spermatogenic potential of oligospermic patients. Thirty-six male patients with oligospermia were enrolled and randomized either to treatment (n = 23) with PHF (750 mg/d in three doses for 90 days) or to placebo (n = 13) in the same protocol. The preintervention semen analysis was compared with posttreatment semen analysis. Based on the postintervention semen analysis, patients were advised to undergo either in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) to assess their fertility status. After polyherbal treatment, there was a 256% increase in sperm concentration (9.59 ± 4.37 × 106/mL to 25.61 ± 8.6 × 10⁶/mL; P ≤0.001), 154% increase in semen volume (1.7 ± 0.14 mL to 4.32 ± 0.38 mL; P ≤0.001), and 215% increase in sperm motility (15.43 ± 2.40% to 48.65 ± 5.10%; P ≤ 0.001) on day 90 from baseline. Furthermore, a significant improvement and regulation were also observed in serum hormone levels with PHF treatment as compared to the placebo group. The present study demonstrated the evidence on synergistic spermatogenic effect of PHF as attributed in ayurveda for the treatment of oligospermia leading to infertility.

Guibourtia tessmannii-induced fictive ejaculation in spinal male rat: involvement of D1, D2-like receptors

CONTEXT

Guibourtia tessmannii (Caesalpiniaceae) is a plant traditionally used as aphrodisiac. We previously reported the pro-ejaculatory effects of the aqueous and methanol extracts of G. tesmannii in spinal male rat. However, the mechanism underlying such effects has not been elucidated.

OBJECTIVE

This study characterizes the dopaminergic sub-type receptors involved in G. tesmannii-induced ejaculation in male Wistar rat.

MATERIALS AND METHODS

Urethane-anesthetized spinal male rats were intravenously treated with saline solution (1 mL/kg, control); dopamine (0.1 μmol/kg, reference); aqueous or methanol extracts of G. tesmannii (20 mg/kg) in the absence or presence of haloperidol (0.26 μmol/kg), a nonspecific dopaminergic receptor antagonist, Sch23390 (0.26 μmol/kg), a specific D1-like receptor antagonist or, sulpiride (0.26 μmol/kg), a specific D2-like receptor antagonist. Electromyography of the bulbospongiosus muscles and intraseminal pressure were recorded after urethral, penile and drug stimulations.

RESULTS

Urethral and penile stimulations, intravenous injection of dopamine or, aqueous and methanol extracts of G. tesmannii always triggered the expression of rhythmic contraction of the bulbospongiosus muscles with an average mean of 3.33 ± 0.43; 7.83 ± 0.85; 9.80 ± 0.86; 0.83 ± 0.54 and 2.67 ± 0.95 contractions, respectively. The intraseminal pressure was more expressed after urethral and penile stimulations (15.66 ± 1.58 and 13.60 ± 2.40 mmHg, respectively). In rats pretreated with haloperidol, Sch23390 or sulpiride, no ejaculation was recorded after intravenous injection of G. tesmannii extracts or dopamine.

DISCUSSION AND CONCLUSION

Guibourtia tesmannii-induced ejaculation requires the integrity of D1 and D2-like receptors. These findings further justify the ethno-medicinal claims of G. tesmannii as an aphrodisiac.

Transcutaneous neuromuscular electrical stimulation may be beneficial in the treatment of premature ejaculation

Approximately 20-30% of sexually active men suffer from Premature Ejaculation (PE), but the pathophysiology still remains unclear and the current available treatments for PE are unsatisfying. Considering the role of rhythmic bulbospongiosus and ischiocavernosus Muscles contractions on the ejaculatory reflex, we hypothesize that weakening this muscles via inhibiting it's contractions by Application of Neuromuscular Electrical Stimulation prior to the planned sexual activity, may have a beneficial effect in the treatment of PE. Using miniaturized perineal on-demand stimulation device, in a home setting during sexual intercourse may become the first line of treatment for PE.

The effect of 8-OH-DPAT and dapoxetine on gene expression in the brain of male rats during ejaculation

The 5-HT_1A receptor agonist 8-hydroxy-2-[di-n-propylamino] tetralin (8-OH-DPAT) promotes ejaculation of male rats, whereas dapoxetine delays this process. However, the gene expression profile of the brain at ejaculation following administrationof these two compounds has not been fully elucidated. In the present study, a transcriptomic BodyMap was generated by conducting mRNA-Seq on brain samples of male Sprague–Dawley rats. The study included four groups: pre-copulatory control (CK) group, ejaculation (EJ) group, 0.5 mg/kg 8-OH-DPAT-ejaculation group (DPAT), and 60 mg/kg dapoxetine-ejaculation (DAP) group. The resulting analysis generated an average of approximately 47 million sequence reads. Significant differences in the gene expression profiles of the aforementioned groups were observed in the EJ (257 genes), DPAT (349 genes) and the DAP (207 genes) compared with the control rats. The results indicate that the expression of Drd1 and Slc6a3 was significantly different after treatment with 8-OH-DPAT, whereas the expression of Drd4 was significantly different after treatment with dapoxetine. Other genes, such as Wnt9b, Cdkn1a and Fosb, exhibited significant differences in expression after the two treatments and are related to bladder cancer, renal cell carcinoma and sexual addiction. The present study reveals the basic pattern of gene expression that was activated at ejaculation in the presence of 8-OH-DPAT or dapoxetine, providing preliminary gene expression information during rat ejaculation.

What is orgasm? A model of sexual trance and climax via rhythmic entrainment

Orgasm is one of the most intense pleasures attainable to an organism, yet its underlying mechanisms remain poorly understood. On the basis of existing literatures, this article introduces a novel mechanistic model of sexual stimulation and orgasm. In doing so, it characterizes the neurophenomenology of sexual trance and climax, describes parallels in dynamics between orgasms and seizures, speculates on possible evolutionary origins of sex differences in orgasmic responding, and proposes avenues for future experimentation. Here, a model is introduced wherein sexual stimulation induces entrainment of coupling mechanical and neuronal oscillatory systems, thus creating synchronized functional networks within which multiple positive feedback processes intersect synergistically to contribute to sexual experience. These processes generate states of deepening sensory absorption and trance, potentially culminating in climax if critical thresholds are surpassed. The centrality of rhythmic stimulation (and its modulation by salience) for surpassing these thresholds suggests ways in which differential orgasmic responding between individuals-or with different partners-may serve as a mechanism for ensuring adaptive mate choice. Because the production of rhythmic stimulation combines honest indicators of fitness with cues relating to potential for investment, differential orgasmic response may serve to influence the probability of continued sexual encounters with specific mates.

Overview of the Anatomy, Physiology, and Pharmacology of the Autonomic Nervous System

Comprised of the sympathetic nervous system, parasympathetic nervous system, and enteric nervous system, the autonomic nervous system (ANS) provides the neural control of all parts of the body except for skeletal muscles. The ANS has the major responsibility to ensure that the physiological integrity of cells, tissues, and organs throughout the entire body is maintained (homeostasis) in the face of perturbations exerted by both the external and internal environments. Many commonly prescribed drugs, over-the-counter drugs, toxins, and toxicants function by altering transmission within the ANS. Autonomic dysfunction is a signature of many neurological diseases or disorders. Despite the physiological relevance of the ANS, most neuroscience textbooks offer very limited coverage of this portion of the nervous system. This review article provides both historical and current information about the anatomy, physiology, and pharmacology of the sympathetic and parasympathetic divisions of the ANS. The ultimate aim is for this article to be a valuable resource for those interested in learning the basics of these two components of the ANS and to appreciate its importance in both health and disease. Other resources should be consulted for a thorough understanding of the third division of the ANS, the enteric nervous system. © 2016 American Physiological Society. Compr Physiol 6:1239-1278, 2016.