Rapid changes in brain aromatase activity in the female quail brain following expression of sexual behaviour

Abstract

In male quail, oestrogens produced in the brain (neuro-oestrogens) exert a dual action on male sexual behaviour: they increase sexual motivation within minutes via mechanisms activated at the membrane but facilitate sexual performance by slower, presumably nuclear-initiated, mechanisms. Recent work indicates that neuro-oestrogens are also implicated in the control of female sexual motivation despite the presence of high circulating concentrations of oestrogens of ovarian origin. Interestingly, aromatase activity (AA) in the male brain is regulated in time domains corresponding to the slow "genomic" and faster "nongenomic" modes of action of oestrogens. Furthermore, rapid changes in brain AA are observed in males after sexual interactions with a female. In the present study, we investigated whether similar rapid changes in brain AA are observed in females allowed to interact sexually with males. A significant decrease in AA was observed in the medial preoptic nucleus after interactions that lasted 2, 5 or 10 minutes, although this decrease was no longer significant after 15 minutes of interaction. In the bed nucleus of the stria terminalis, a progressive decline of average AA was observed between 2 and 15 minutes, although it never reached statistical significance. AA in this nucleus was, however, negatively correlated with the sexual receptivity of the female. These data indicate that sexual interactions affect brain AA in females as in males in an anatomically specific manner and suggest that rapid changes in brain oestrogens production could also modulate female sexual behaviour.

Steroid Transport, Local Synthesis, and Signaling within the Brain: Roles in Neurogenesis, Neuroprotection, and Sexual Behaviors

“…It should be noted that the measurements of estrogens do not correlate with aromatase activity in most cases and future work should tackle this discrepancy (Charlier et al, 2011b ; Dickens et al, 2014 ; de Bournonville et al, 2017b ). Interestingly, central aromatase is not only important for male sexual behavior but was also shown recently to be involved in female sexual behavior in Japanese quail (de Bournonville et al, 2016 , 2017a ), see also recent discussion in Cornil ( 2017 ). The very high concentration of aromatase in birds make them a very suitable model to investigate its function in modulating sexual behavior but it is likely that rapid change in aromatase activity are also important in mammals and fish, as rapid effects of estrogens were demonstrated on sexual motivation in rat and Goldfish (Cross and Roselli, 1999 ).…”

On the role of brain aromatase in females: why are estrogens produced locally when they are available systemically?

“…Aromatase activity is up-regulated in the POM and down-regulated in the tuberal hypothalamus of females within minutes of acute restraint stress (Fig.3a) (Dickens et al 2011; Dickens et al 2012). By contrast, an interaction with a sexually active male results in a decreased activity in the POM (de Bournonville et al 2017b). Importantly, aromatase activity positively correlates with tissue content in estradiol in both the POA and the MBH, regardless of whether females had been stressed or paired with a male partner (Fig.…”

Aromatase and nonaromatase neurons in the zebra finch secondary auditory forebrain are indistinct in their song‐driven gene induction and intrinsic electrophysiological properties

“…Interestingly, telencephalic aromatase activity is rapidly regulated by phosphorylating conditions in zebra finches, particularly within synaptosomes (Comito et al, 2016;Cornil et al, 2012). A line of work in Japanese quail has shown that aromatase activity is also sensitive to environmental stimulation (sex interaction or stress) in both males and females (Cornil et al, 2005;de Bournonville et al, 2013de Bournonville et al, , 2017Dickens et al, 2011Dickens et al, , 2014. These effects occur within very short time scales (2-5 min).…”

“…Neuroestrogens are important neuromodulators that regulate social communication and other sexual behaviors (Balthazart et al, 2018;Cornil & de Bournonville, 2018;de Bournonville et al, 2017;Vahaba & Remage-Healey, 2018). The production and local action of neuroestrogens is key for auditory processing in songbirds.…”