Preferencias condicionadas por sexo y drogas: Una comparación de las bases neurales

Objetivo. Realizar una comparación comportamental y neurobiológica de las preferencias condicionadas de pareja inducidas por sexo y las condicionadas por drogas en modelos de estudio llevados a cabo en animales de laboratorio. Desarrollo. Las preferencias condicionadas por sexo o por consumo de drogas tienen similitudes. En ambos procesos se aprende a asociar cambios de estado fisiológico y subjetivo a lo que se denomina recompensa con estímulos ambientales, induciendo así la formación de preferencias aprendidas, lo que ha llevado a pensar que tanto las preferencias de pareja que aparecen después de encuentros sexuales como el consumo repetido de drogas dependen, al menos en parte, del condicionamiento clásico que ocurre por la asociación de estímulos condicionados y la recompensa. Además, en ambos procesos se activan áreas cerebrales mesolímbicas que dependen de los mismos neurotransmisores, como la dopamina, los opioides y la oxitocina, entre otros. Agonistas de éstos facilitan el desarrollo de preferencias condicionadas y los antagonistas afectan a su desarrollo. Conclusiones. Los datos en animales experimentales sugieren que las preferencias condicionadas por drogas utilizan mecanismos cerebrales involucrados en la recompensa sexual. Dichos mecanismos se activan para detectar y aprender a buscar estímulos como los sexuales, importantes para la supervivencia y la reproducción

Inhibition of lysine-specific demethylase enzyme disrupts sexually conditioned mate guarding in the female rat

Although female rats are typically described as having a promiscuous mating strategy, if sexually naïve females have their formative sexually rewarding experiences paired with the same male, they will recognize that male and display mate-guarding behavior towards him in the presence of a female competitor. Female rats that display mate guarding behavior also show enhanced activation of oxytocin and vasopressin neurons in the supraoptic and paraventricular hypothalamic nucleus. Here, we examined the potential role that histone demethylation might have in establishing this pair-bonded behavior, and whether the corresponding changes in oxytocin and vasopressin neuronal activation depended on demethylation. To accomplish this, we examined the effect of a lysine-specific demethylase-1 inhibitor to block the action of demethylase enzymes and maintain the methylation state of corresponding genes. Female rats treated with the demethylase inhibitor failed to show any measure of mate guarding, whereas females treated with vehicle displayed mate guarding behavior. Demethylase inhibitor treatment also blocked the ability of familiar male cues to activate oxytocin and vasopressin neurons, whereas vehicle-treated females showed this enhanced activation. These data indicate that histone demethylation is a crucial component in the epigenetic modification of neural circuitry that underlies conditioned mate guarding in female rats. These results are the first to demonstrate the role of histone demethylation underlying changes in mating strategy

Neurobiology of social attachments

Many types of social attachments can be observed in nature. We discuss the neurobiology of two types (1) intraspecific (with a partner) and (2) parental (with the offspring). Stimuli related to copulation facilitate the first, whereas pregnancy, parturition and lactation facilitate the second. Both types develop as consequence of cohabitation. These events seem to stimulate similar neural pathways that increase (1) social recognition, (2) motivation, reward; and (3) decrease fear/anxiety. Subregions of the amygdala and cortex facilitate social recognition and also disinhibition to decrease rejection responses. The interrelationship between MeA, BNST, LS may mediate the activation of NAcc via the mPOA to increase motivation and reward. Cortical areas such as the ACC discriminate between stimuli. The interaction between OT and D2-type receptors in NAcc shell facilitates intraspecific attachment, but D1-type appears to facilitate parental attachment. This difference may be important for maternal females to direct their attention, motivation and expression of attachment toward the appropriate target.Cuerpo Académico UV-CA-28 Neurociencias. Grant SEP-CONACYT (167773) to GACA

Reply to: Are stressful childhood experiences relevant in non monosexual women?

We thank the commentator for his thoughtful response (Schneeberger, 2015) to our study entitled, “Explaining Mental Health Disparities for Non-monosexual Women: Abuse History and Risky Sex, or the Burdens of Non-disclosure?” (Persson et al., 2014) To summarize, Schneeberger (2015) highlights three aspects of our methodological approach: (1) how the participants were grouped; (2) how sexual orientation was evaluated; and (3) how a history of childhood abuse was assessed. We will reflect on these three issues while further considering future research directions in the study of female sexual orientation and childhood abuse

Hypoactive Sexual Desire Disorder:International Society for the Study of Women's Sexual Health (ISSWSH) Expert Consensus Panel Review

The objective of the International Society for the Study of Women\u27s Sexual Health expert consensus panel was to develop a concise, clinically relevant, evidence-based review of the epidemiology, physiology, pathogenesis, diagnosis, and treatment of hypoactive sexual desire disorder (HSDD), a sexual dysfunction affecting approximately 10% of adult women. Etiologic factors include conditions or drugs that decrease brain dopamine, melanocortin, oxytocin, and norepinephrine levels and augment brain serotonin, endocannabinoid, prolactin, and opioid levels. Symptoms include lack or loss of motivation to participate in sexual activity due to absent or decreased spontaneous desire, sexual desire in response to erotic cues or stimulation, or ability to maintain desire or interest through sexual activity for at least 6 months, with accompanying distress. Treatment follows a biopsychosocial model and is guided by history and assessment of symptoms. Sex therapy has been the standard treatment, although there is a paucity of studies assessing efficacy, except for mindfulness-based cognitive behavior therapy. Bupropion and buspirone may be considered off-label treatments for HSDD, despite limited safety and efficacy data. Menopausal women with HSDD may benefit from off-label testosterone treatment, as evidenced by multiple clinical trials reporting some efficacy and short-term safety. Currently, flibanserin is the only Food and Drug Administration-approved medication to treat premenopausal women with generalized acquired HSDD. Based on existing data, we hypothesize that all these therapies alter central inhibitory and excitatory pathways. In conclusion, HSDD significantly affects quality of life in women and can effectively be managed by health care providers with appropriate assessments and individualized treatments

Persistent Genital Arousal Disorder (PGAD): case report of long-term symptomatic management with electroconvulsive therapy

Introduction. This is the second case report of a woman with bipolar disorder type I who noted the onset of persistent genital arousal disorder (PGAD) symptoms after abrupt cessation of paroxetine. With the worsening of PGAD symptoms, she developed severe depression and suicidal thoughts, resulting in her undergoing electroconvulsive therapy (ECT) as management. Aim. To describe a case of PGAD and develop hypotheses to explain the beneficial actions of ECT on PGAD based on 4 years of ECT administration. Methods. Patient self-report after obtaining consent, as well as literature review. Results. After the fourth ECT, the patient's PGAD symptoms abated serendipitously. She was placed on ECT on demand for the treatment of her PGAD. With each ECT treatment, PGAD symptoms immediately disappeared, relapsing slowly over time until the next ECT was administered. The patient has, thus far, received a total of 30 treatments of ECT. Side effects continue to be minimal and include brief short-term memory loss, headache, and muscle aches. Conclusion. ECT is known to induce cerebral excitatory and inhibitory neurotransmitter changes after acute and chronic administration. Sexual arousal is stimulated by the action of hypothalamic and limbic dopamine, noradrenaline, melanocortin, and oxytocin, and inhibited by serotonin, cerebral opioids, and endocannabinoids. Based on the patient's bipolar disorder, the mechanism of action of ECT and the observation of ECT effectiveness on her PGAD, we hypothesize the following: (i) bipolar disorder led to central hyperactive dopamine release, an important component in the pathophysiology of her PGAD; (ii) central serotonin deficiency after selective serotonin-reuptake inhibitor (SSRI) withdrawal resulted in a lack of inhibition of sexual excitement; (iii) ECT resulted in lowering of the hyperstimulated central dopamine release; and (iv) ECT led to an increase in sexual inhibition by stimulating serotonin activity

Colocalization of tyrosine hydroxylase and Fos in the male Syrian hamster brain following different states of arousal

In an investigation of the role that central tyrosine hydroxylase-(TH) containing neurons play in copulation in the male Syrian hamster, The induction of Fos protein was used as an index of neuronal activation. With a double immunoperoxidase technique, the activation of TH neurons was compared in hamsters from three experimental groups: (1) mated in a new cage; (2) handled controls placed in a new cage, and (3) unhandled controls. Although mating selectively induces Fos production in the medial amygdaloid nucleus (Me), more than half of the TH neurons in Me (a region outside of the classical catecholamine systems) expressed Fos equally in all of the experimental groups. In the paraventricular hypothalamic nucleus (PVN), TH neurons were activated equivalently in mated and handled control animals compared to unhandled controls. TH neurons in the neucleus of the solitary tract (NST) were also activated in handled control animals, and mating further enhanced the level of Fos immunostaining in these neurons above both groups of nonmated animals. Although not quantified, co-localization of Fos and TH was also observed in all experimental groups in the olfactory bulbs and the interfascicular nucleus, and in the horizontal limb of the diagonal band of Broca and the cerebral cortex, regions which contain TH neurons but are not part of the classically described TH cell groups. Few, if any, TH neurons in other catecholaminergic brain regions, such as the substantia nigra and locus coeruleus, produced Fos in any of the experimental groups. These results suggest that TH neurons in the PVN and NST may be activated during different states of arousal, and that nonclassical TH neurons in the amygdala produce high levels of Fos even in unstimulated animals. 1994 John Wiley & Sons, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50083/1/480250207_ftp.pd

Diurnal rhythms in neural activation in the mesolimbic reward system: critical role of the medial prefrontal cortex

Previous evidence suggests a circadian modulation of drug‐seeking behavior and responsiveness to drugs of abuse. To identify potential mechanisms for rhythmicity in reward, a marker of neural activation (c F os) was examined across the day in the mesolimbic reward system. Rats were perfused at six times during the day [zeitgeber times ( ZT s): 2, 6, 10, 14, 18, and 22], and brains were analysed for c F os and tyrosine hydroxylase ( TH )‐immunoreactive ( IR ) cells. Rhythmic expression of c F os was observed in the nucleus accumbens ( NA c) core and shell, in the medial prefrontal cortex (m PFC ), and in TH ‐ IR and non‐ TH ‐ IR cells in the ventral tegmental area ( VTA ), with peak expression during the late night and nadirs during the late day. No significant rhythmicity was observed in the basolateral amgydala or the dentate gyrus. As the m PFC provides excitatory input to both the NA c and VTA , this region was hypothesised to be a key mediator of rhythmic neural activation in the mesolimbic system. Hence, the effects of excitotoxic m PFC lesions on diurnal rhythms in c F os immunoreactivity at previously observed peak ( ZT 18) and nadir ( ZT 10) times were examined in the NA c and VTA . m PFC lesions encompassing the prelimbic and infralimbic subregions attenuated peak c F os immunoreactivity in the NA c, eliminating the diurnal rhythm, but had no effect on VTA rhythms. These results suggest that rhythmic neural activation in the mesolimbic system may contribute to diurnal rhythms in reward‐related behaviors, and indicate that the m PFC plays a critical role in mediating rhythmic neural activation in the NA c. Previous evidence suggests a circadian modulation of drug‐seeking behavior and responsiveness to drugs of abuse. To identify potential mechanisms for rhythmicity in reward, a maker of neural activation (c F os) was examined across the day in the mesolimbic reward system.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/99016/1/ejn12224.pd