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Orsay, France

Delgadillo J.A.,Antonio Narro Agrarian Autonomous University | Vielma J.,Antonio Narro Agrarian Autonomous University | Hernandez H.,Antonio Narro Agrarian Autonomous University | Flores J.A.,Antonio Narro Agrarian Autonomous University | And 4 more authors.
Hormones and Behavior | Year: 2012

We investigated whether live vocalizations emitted by bucks interacting with anestrous females stimulate secretion of LH, estrous behavior and ovulation in anestrous goats. In experiment 1, bucks rendered sexually active by exposure to long days followed by natural photoperiod were exposed in a light-proof-building to five anestrous females. Buck vocalizations were reproduced through a microphone-amplifier-loudspeaker system to an open pen where one group of goats (n = 6) was exposed for 10 days to these live vocalizations. Another group of females (n = 6) was isolated from males and vocalizations. The proportion of goats displaying estrous behavior was significantly higher in females exposed to buck vocalizations than in females isolated from males. The proportion of goats that ovulated did not differ between the 2 groups (exposed to males versus isolated). In experiment 2, female goats that either had previous contact with males (n = 7), or no previous contact with males (n = 7) were exposed to live buck vocalizations, reproduced as described in experiment 1, for 5 days. The number and amplitude of LH pulses did not differ between groups before exposition to buck vocalizations. Five days of exposure to male vocalizations significantly increased LH pulsatility only in females that had previous contact with males, while LH pulse amplitude was not modified. We concluded that live buck vocalizations can stimulate estrous behavior and LH secretion in goats if they have had previous contact with bucks. © 2012 Elsevier Inc.

Fernandez I.G.,Antonio Narro Agrarian Autonomous University | Luna-Orozco J.R.,Antonio Narro Agrarian Autonomous University | Vielma J.,Antonio Narro Agrarian Autonomous University | Duarte G.,Antonio Narro Agrarian Autonomous University | And 4 more authors.
Hormones and Behavior | Year: 2011

We investigated whether LH secretion, estrous behavior and fertility would differ between sexually inexperienced and experienced anestrous goats exposed to the males. Male goats were rendered sexually active during the reproductive rest season by exposure to 2.5. months of artificial long days. Two groups of anovulatory sexually inexperienced and sexually experienced does were exposed to males during 15 days (n = 20 per group). LH pulsatility was determined every 15 min from 4 h before to 8 h after introducing males (Day 0). Estrous behavior was recorded twice daily. Pregnancy rates were determined on Day 50. Fertility was determined at parturition. Male sexual behavior was registered on days 1 and 2 during 1 h. Before introducing the males, the number of LH pulses did not differ between groups. After introduction of the males, all females increased their LH pulsatility, but the number of pulses did not differ between sexually inexperienced and experienced goats. The proportion of females displaying estrous behavior with a high pregnancy rate and fertility did not differ between inexperienced and experienced goats. The sexual behavior of the males did not differ significantly between those interacting with sexually inexperienced or experienced goats. We conclude that goats can show substantial endocrine and reproductive responses to males, even in the absence of previous sexual experience, when sexually active bucks are used. © 2011 Elsevier Inc.

Gelez H.,Pelvipharm Laboratories | Poirier S.,Pelvipharm Laboratories | Facchinetti P.,French Institute of Health and Medical Research | Allers K.A.,Boehringer Ingelheim | And 5 more authors.
Journal of Chemical Neuroanatomy | Year: 2010

The melanocortin-4 receptor (MC4-R) plays a critical role in several physiological functions, from food intake, energy homeostasis, neuroendocrine and cardiovascular function, to sexual responses. The brain regions and the central neuronal pathways mediating the different actions of MC4-R remain largely unknown. We aimed to use immunocytochemistry using a specific antibody against rat MC4-R, to establish the detailed neuroanatomical distribution of MC4-R in brain slices of male and estrous female rats. We demonstrated that MC4-R-positive neurons were widely distributed in several brain regions including the cortex, thalamus, hypothalamus, and brainstem. In both male and female brains, MC4-R-positive cells were especially abundant in the hypothalamus, including the paraventricular hypothalamic nucleus, lateral septal nucleus, arcuate nucleus, supraoptic nucleus, medial preoptic area and lateral hypothalamic area. A moderate number of MC4-R-positive neurons were found in the piriform cortex, bed nucleus of the stria terminalis, medial and basolateral nuclei of amygdala, periaqueductal gray, red nucleus and raphe nucleus. A dimorphic sexual difference in the number of MC4-R-positive neurons was observed in some brain regions. In the medial preoptic area and arcuate nucleus, MC4-R-positive neurons were significantly more abundant in female than in males, whereas in the lateral hypothalamus the opposite proportion was observed. This is the first time the neuroanatomical distribution, and sex differences, of brain MC4-R localisation have been described. The distribution of MC4-R is consistent with the proposed roles of MC4-R-positive neurons and provides further information about the circuitry controlling food intake, energy balance and sexual responses in both males and females. © 2010 Elsevier B.V.

Gelez H.,Pelvipharm Laboratories | Poirier S.,Pelvipharm Laboratories | Allers K.A.,Boehringer Ingelheim | Wayman C.,Pfizer | And 3 more authors.
Journal of Sexual Medicine | Year: 2010

Introduction.: The clitoris and the vagina are the main peripheral anatomical structures involved in physiological changes related to sexual arousal and orgasm. Their efferent control and, more particularly, the neurochemical phenotype of these descending neuronal pathways remain largely uncharacterized. Aim.: To examine if brain neurons involved in the efferent control of the clitoris and the vagina possess melanocortin-4 receptor (MC4-R) and/or contain oxytocin (OT). Methods.: Neurons involved in the efferent control of the vagina and clitoris were identified following visualization of pseudorabies virus (PRV) retrograde tracing. PRV was injected into the vagina and clitoris in adult rats in estrous. On the fifth day postinjection, animals were humanely sacrificed, and brains were removed and sectioned, and processed for PRV visualization. The neurochemical phenotype of PRV-positive neurons was identified using double or triple immunocytochemical labeling against PRV, MC4-R, and OT. Double and triple labeling were quantified using confocal laser scanning microscopy. Main Outcome Measure.: Neuroanatomical brain distribution, number and percentage of double-labeled PRV/MC4-R and PRV-/OT-positive neurons, and triple PRV-/MC4-R-/OT-labeled neurons. Results.: The majority of PRV immunopositive neurons which also expressed immunoreactivity for MC4-R were located in the paraventricular and arcuate nuclei of the hypothalamus. The majority of PRV positive neurons which were immunoreactive (IR) for OT were located in the paraventricular nucleus (PVN), medial preoptic area (MPOA), and lateral hypothalamus. PRV positive neurons were more likely to be IR for MC4-R than for OT. Scattered triple-labeled PRV/MC4-R/OT neurons were detected in the MPOA and the PVN. Conclusion.: These data strongly suggest that MC4-R and, to a less extent, OT are involved in the efferent neuronal control of the clitoris and vagina, and consequently facilitate our understanding of how the melanocortinergic pathway regulates female sexual function. © 2010 International Society for Sexual Medicine.

Giuliano F.,Neuro Uro Andrology | Giuliano F.,Pelvipharm Laboratories | Giuliano F.,University of Versailles | Clcment P.,Pelvipharm Laboratories | Clcment P.,University of Versailles
Pharmacological Reviews | Year: 2012

Male sexual response comprises four phases: excitement, including erection; plateau; ejaculation, usually accompanied by orgasm; and resolution. Ejaculation is a complex sexual response involving a sequential process consisting of two phases: emission and expulsion. Ejaculation, which is basically a spinal reflex, requires a tight coordination between sympathetic, parasympathetic, and somatic efferent pathways originating from different segments and area in the spinal cord and innervating pelviperineal anatomical structures. A major relaying and synchronizing role is played by a group of lumbar neurons described as the spinal generator of ejaculation. Excitatory and inhibitory influences from sensory genital and cerebral stimuli are integrated and processed in the spinal cord. Premature ejaculation (PE) can be defined by <1-min ejaculatory latency, an inability to delay ejaculation, and negative personal consequences. Because there is no physiological impairment in PE, any pharmacological agent with central or peripheral mechanism of action that is delaying the ejaculation is a drug candidate for the treatment of PE. Ejaculation is centrally mediated by a variety of neurotransmitter systems, involving especially serotonin and serotonergic pathways but also dopaminergic and oxytocinergic systems. Pharmacological delay of ejaculation can be achieved either by inhibiting excitatory or reinforcing inhibitory pathways from the brain or the periphery to the spinal cord. PE can be treated with long-term use of selective serotoninreuptake inhibitors (SSRIs) or tricyclic antidepressants. Dapoxetine, a short-acting SSRI, is the first treatment registered for the on-demand treatment of PE. Anesthetics applied on the glans penis have the ability to lengthen the time to ejaculation. Targeting oxytocinergic, neurokinin-1, dopaminergic, and opioid receptors represent future avenues to delaying ejaculation. © 2012 by The American Society for Pharmacology and Experimental Therapeutics.

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