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1.
J Sex Med ; 14(9): 1116-1124, 2017 09.
Article in English | MEDLINE | ID: mdl-28807505

ABSTRACT

BACKGROUND: Although delayed ejaculation (DE) is typically characterized as a persistently longer than anticipated or desired time to ejaculation (or orgasm) during sexual activity, a timing-based definition of DE and its association with serum testosterone has not been established in a large cohort. AIM: To examine in an observational study estimated intravaginal ejaculatory latency time (IELT) and masturbatory ejaculation latency time (MELT) in men self-reporting DE, assess the association of IELT and MELT with serum testosterone levels, and determine whether correlation with demographic and sexual parameters exist. METHODS: Men who resided in the United States, Canada, and Mexico were enrolled from 2011 to 2013. Self-estimated IELT and MELT were captured using an Ejaculatory Function Screening Questionnaire in a sample of 988 men screened for possible inclusion in a randomized clinical trial assessing testosterone replacement therapy for ejaculatory dysfunction (EjD) and who self-reported the presence or absence of DE and symptoms of hypogonadism. Additional comorbid EjDs (ie, anejaculation, perceived decrease in ejaculate volume, and decreased force of ejaculation) were recorded. Men with premature ejaculation were excluded from this analysis. IELT and MELT were compared between men self-reporting DE and men without DE. The associations of IELT and MELT with serum testosterone were measured. OUTCOMES: IELT, MELT, and total testosterone levels. RESULTS: Sixty-two percent of screened men self-reported DE with or without comorbid EjDs; 38% did not report DE but did report at least one of the other EjDs. Estimated median IELTs were 20.0 minutes for DE vs 15 minutes for no DE (P < .001). Estimated median MELTs were 15.0 minutes for DE vs 8.0 minutes for no DE (P < .001). Ejaculation time was not associated with serum testosterone levels. Younger men and those with less severe erectile dysfunction had longer IELTs and MELTs. CLINICAL IMPLICATIONS: Estimated ejaculation times during vaginal intercourse and/or masturbation were not associated with serum testosterone levels in this study; thus, routine androgen evaluation is not indicated in these men. STRENGTHS AND LIMITATIONS: This large systematic analysis attempted to objectively assess the ejaculation latency in men with self-reported DE. Limitations were that ejaculation time estimates were self-reported and were queried only once; the questionnaire did not distinguish between failure to achieve orgasm and ejaculation; and assessment of DE was limited to heterosexual vaginal intercourse and masturbation. CONCLUSION: IELT and MELT were longer in men with DE, and there was no association of ejaculation times with serum testosterone levels in this study population. Morgentaler A, Polzer P, Althof S, et al. Delayed Ejaculation and Associated Complaints: Relationship to Ejaculation Times and Serum Testosterone Levels. J Sex Med 2017;14:1116-1124.


Subject(s)
Erectile Dysfunction/drug therapy , Testosterone/blood , Adult , Canada , Erectile Dysfunction/physiopathology , Erectile Dysfunction/psychology , Hormone Replacement Therapy , Humans , Male , Mexico , Middle Aged , Orgasm , Penile Erection , Self Report , Surveys and Questionnaires , Testosterone/therapeutic use , Time Factors
2.
J Sex Med ; 13(8): 1212-9, 2016 08.
Article in English | MEDLINE | ID: mdl-27329542

ABSTRACT

INTRODUCTION: Evidence from well-designed studies documenting the benefit of testosterone replacement therapy as a function of patient demographic and clinical characteristics is lacking. AIM: To determine demographic and clinical predictors of treatment outcomes in hypogonadal men with low sex drive, low energy, and/or erectile dysfunction. METHODS: Post hoc analysis of a randomized, multicenter, double-blinded, placebo-controlled, 16-week study of 715 hypogonadal men (mean age = 55.3 years, age range = 19-92 years) presenting with low sex drive and/or low energy who received placebo or testosterone solution 2% for 12 weeks. MAIN OUTCOMES AND MEASURES: Two levels defined patient-reported improvement (PRI) in sex drive or energy: level 1 was at least "a little better" and level 2 was at least "much better" in energy or sex drive on the Patient Global Impression of Improvement at study end point. PRI in erectile function was stratified by erectile dysfunction severity at baseline as measured by the erectile function domain of the International Index for Erectile Function: mild at baseline (change of 2), moderate at baseline (change of 5), and severe at baseline (change of 7). Associations of demographic and clinical characteristics with PRI were calculated with stepwise forward multiple logistic regression analysis. Odds ratios represented the likelihood of PRI in symptoms among variable categories. RESULTS: Higher levels of end-point testosterone were associated with higher rates of PRI (at levels 1 and 2) in sex drive and energy (P < .001 for the two comparisons). Lower baseline testosterone levels were associated with higher rates of level 1 PRI in sex drive (P = .028); and classic hypogonadism (vs non-classic hypogonadism) was associated with higher rates of level 2 PRI in sex drive (P = .005) and energy (P = .006). CONCLUSION: When assessing the potential for improvements in men with testosterone deficiency using patient-reported outcome questionnaires, possible predictors of treatment outcomes to consider include the etiology of hypogonadism and testosterone levels (baseline and end point).


Subject(s)
Androgens/therapeutic use , Hypogonadism/drug therapy , Testosterone/therapeutic use , Adult , Aged , Aged, 80 and over , Demography , Double-Blind Method , Erectile Dysfunction/etiology , Humans , Libido/drug effects , Male , Middle Aged , Patient Reported Outcome Measures , Penile Erection/drug effects , Quality of Life , Surveys and Questionnaires , Treatment Outcome , Young Adult
3.
J Sex Med ; 12(12): 2276-86, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26511106

ABSTRACT

INTRODUCTION: Ejaculatory dysfunctions other than premature ejaculation are commonly encountered in specialized clinics; however, their characterization in community-dwelling men is lacking. AIM: The aim of this study was to evaluate the prevalence, severity, and associated distress of four ejaculatory dysfunctions: delayed ejaculation (DE), anejaculation (AE), perceived ejaculate volume reduction (PEVR) and/or decreased force of ejaculation (DFE) as a function of demographic and clinical characteristics in men. METHODS: Observational analysis of 988 subjects presenting with one or more types of ejaculatory dysfunctions other than premature ejaculation who screened for a randomized clinical trial assessing the efficacy of testosterone replacement on ejaculatory dysfunction. Demographic and clinical characteristics were assessed as potential risk factors using regression analysis. MAIN OUTCOME MEASURES: The main outcome measures used were ejaculatory dysfunction prevalence and scores (3-item Men's Sexual Health Questionnaire Ejaculatory Dysfunction-Short Form [MSHQ-EjD-SF]), and bother (MSHQ-EjD-SF Bother item) and sexual satisfaction/enjoyment (International Index of Erectile Function Questionnaire Q7, Q8) as a function of subject's age, race, body mass index (BMI) and serum testosterone levels (measured by liquid chromatography tandem mass spectrometry). RESULTS: Mean (standard deviation [SD]) age of the participants was 52 years (11). Eighty-eight percent of the men experienced more than one type of ejaculatory dysfunction and 68% considered their symptoms to be bothersome. Prevalence of the ejaculatory dysfunctions was substantial across a range of age, race, BMI, and serum testosterone categories. Prevalence of PEVR and DFE were positively associated with age (<40 years vs. 60-70 years: PEVR: odds ratio [OR], 3.05; 95% confidence interval [CI], 1.32-7.06; DFE: OR, 2.78; 95% CI, 1.46-5.28) while DFE was associated with BMI (≥30 kg/m(2) vs. < 25 kg/m(2) : OR, 1.80; 95% CI, 1.062-3.05). All ejaculatory dysfunctions were more prevalent in black men. CONCLUSION: The majority of the participants experienced multiple ejaculatory dysfunctions and found them to be highly bothersome. Ejaculatory dysfunctions were prevalent across a wide range of demographic and clinical characteristics.


Subject(s)
Androgens/blood , Erectile Dysfunction/physiopathology , Men's Health , Testosterone/blood , Adult , Age Factors , Aged , Androgens/therapeutic use , Ejaculation , Erectile Dysfunction/epidemiology , Erectile Dysfunction/etiology , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Personal Satisfaction , Prevalence , Prospective Studies , Risk Assessment , Risk Factors , Surveys and Questionnaires , Testosterone/therapeutic use
4.
J Neurophysiol ; 113(3): 786-95, 2015 Feb 01.
Article in English | MEDLINE | ID: mdl-25392167

ABSTRACT

Both short- and long-term roles for the group I metabotropic glutamate receptor number 5 (mGluR5) have been examined for the regulation of cortical glutamatergic synapses. However, how mGluR5 sculpts neocortical networks during development still remains unclear. Using a single cell deletion strategy, we examined how mGluR5 regulates glutamatergic synaptic pathways in neocortical layer 2/3 (L2/3) during development. Electrophysiological measurements were made in acutely prepared slices to obtain a functional understanding of the effects stemming from loss of mGluR5 in vivo. Loss of postsynaptic mGluR5 results in an increase in the frequency of action potential-independent synaptic events but, paradoxically, results in a decrease in evoked transmission in two separate synaptic pathways providing input to the same pyramidal neurons. Synaptic transmission through α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, but not N-methyl-d-aspartate (NMDA) receptors, is specifically decreased. In the local L2/3 pathway, the decrease in evoked transmission appears to be largely due to a decrease in cell-to-cell connectivity and not in the strength of individual cell-to-cell connections. This decrease in evoked transmission correlates with a decrease in the total dendritic length in a region of the dendritic arbor that likely receives substantial input from these two pathways, thereby suggesting a morphological correlate to functional alterations. These changes are accompanied by an increase in intrinsic membrane excitability. Our data indicate that total mGluR5 function, incorporating both short- and long-term processes, promotes the strengthening of AMPA receptor-mediated transmission in multiple neocortical pathways.


Subject(s)
Neocortex/metabolism , Pyramidal Cells/metabolism , Receptor, Metabotropic Glutamate 5/metabolism , Receptors, AMPA/metabolism , Synaptic Transmission , Animals , Dendrites/metabolism , Dendrites/physiology , Mice , Mice, Inbred C57BL , Neocortex/cytology , Neocortex/growth & development , Neocortex/physiology , Pyramidal Cells/physiology , Receptor, Metabotropic Glutamate 5/genetics
5.
J Neurosci ; 34(9): 3413-8, 2014 Feb 26.
Article in English | MEDLINE | ID: mdl-24573297

ABSTRACT

Pruning of structural synapses occurs with development and learning. A deficit in pruning of cortical excitatory synapses and the resulting hyperconnectivity is hypothesized to underlie the etiology of fragile X syndrome (FXS) and related autistic disorders. However, clear evidence for pruning in neocortex and its impairment in FXS remains elusive. Using simultaneous recordings of pyramidal neurons in the layer 5A neocortical network of the wild-type (WT) mouse to observe cell-to-cell connections in isolation, we demonstrate here a specific form of "connection pruning." Connection frequency among pyramidal neurons decreases between the third and fifth postnatal weeks, indicating a period of connection pruning. Over the same interval in the FXS model mouse, the Fmr1 knock-out (KO), connection frequency does not decrease. Therefore, connection frequency in the fifth week is higher in the Fmr1 KO compared with WT, indicating a state of hyperconnectivity. These alterations are due to postsynaptic deletion of Fmr1. At early ages (2 weeks), postsynaptic Fmr1 promoted the maturation of cell-to-cell connections, but not their number. These findings indicate that impaired connection pruning at later ages, and not an excess of connection formation, underlies the hyperconnectivity in the Fmr1 KO mouse. FMRP did not appear to regulate synapses individually, but instead regulated cell-to-cell connectivity in which groups of synapses mediating a single cell-to-cell connection are uniformly removed, retained, and matured. Although we do not link connection pruning directly to the pruning of structurally defined synapses, this study nevertheless provides an important model system for studying altered pruning in FXS.


Subject(s)
Cell Communication/genetics , Fragile X Syndrome/pathology , Neocortex/pathology , Nerve Net/physiology , Pyramidal Cells/physiology , Synapses/genetics , Animals , Animals, Newborn , Disease Models, Animal , Excitatory Amino Acid Agents/pharmacology , Excitatory Postsynaptic Potentials/drug effects , Excitatory Postsynaptic Potentials/genetics , Female , Fragile X Mental Retardation Protein/genetics , Fragile X Syndrome/genetics , Glycine/pharmacology , Glycine Agents/pharmacology , Green Fluorescent Proteins/genetics , In Vitro Techniques , Male , Mice , Mice, Transgenic , Nerve Net/cytology , Pyramidal Cells/drug effects , Quinoxalines/pharmacology , Synapses/drug effects , Synapses/physiology
6.
J Neurosci ; 33(6): 2593-604, 2013 Feb 06.
Article in English | MEDLINE | ID: mdl-23392687

ABSTRACT

In the mouse model of Fragile X syndrome, the Fmr1 knock-out, local excitation of layer 4 fast-spiking (FS) inhibitory neurons is robustly decreased by 50%, but the mechanisms mediating this change are unknown. Here, we performed recordings in acutely prepared slices obtained from Fmr1 "mosaic" mice, where Fmr1 is deleted in about half of all neurons, and we found that loss of presynaptic, but not postsynaptic, Fmr1 fully recapitulates the deficit. The change in connection strength is primarily due to a decrease in release probability indicating that FMRP normally positively regulates these processes. This change in presynaptic neurotransmitter release is observed both in the mosaic mice and in the constitutive Fmr1 knock-out mice. Manipulations in release probability enabled both the mimic and rescue of the impaired function in this synaptic pathway. Loss of presynaptic Fmr1 has no effect on excitatory synapses onto excitatory neurons, indicating a target cell-specific function for presynaptic FMRP. Finally, we demonstrate that the excitation decrement onto FS neurons also exists in layer 5 of the Fmr1 knock-out, suggesting a widespread role for presynaptic Fmr1 in the excitation of inhibitory neurons. In summary, we identify a novel function for presynaptic FMRP in promoting presynaptic neurotransmitter release, and we show that loss of this function accounts for impaired excitation of neocortical FS inhibitory neurons. These changes may contribute to the cognitive dysfunction and circuit hyperexcitability associated with Fragile X syndrome, including patients with complete deletion of FMRP and those with mosaic expression of FMRP.


Subject(s)
Action Potentials/physiology , Fragile X Mental Retardation Protein/physiology , Glutamic Acid/metabolism , Neocortex/metabolism , Neural Inhibition/physiology , Presynaptic Terminals/metabolism , Action Potentials/drug effects , Animals , Dizocilpine Maleate/pharmacology , Excitatory Postsynaptic Potentials/drug effects , Excitatory Postsynaptic Potentials/physiology , Female , Inhibitory Postsynaptic Potentials/drug effects , Inhibitory Postsynaptic Potentials/physiology , Male , Mice , Mice, Inbred C57BL/physiology , Mice, Knockout , Mice, Transgenic , Neocortex/drug effects , Neural Inhibition/drug effects , Neurons/drug effects , Neurons/metabolism , Presynaptic Terminals/drug effects , Time Factors
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