Summary: New research has discovered how a mouse’s serotonin tuned brain circuit affects sex-specific mating behaviors. A set of prefrontal cortex neurons, according to scientists, combine oxytocin, ovarian hormones, and social cues to regulate female genital receptivity and prevent male mating interest.
When these neurons were activated during gestation, activating them prevented non-fertile females from becoming fertile, while silencing them prevented male interest. The findings demonstrate how, depending on physiological conditions, similar brain circuits can cause significantly unique behaviors in men and women.
Important Information
- Hormone-Responsive Circuit: Oxytocin and ovarian hormone signals are incorporated into the frontal cortex’s cerebral cortex’s hormone-responsive circuit, which controls sociosexual behaviors.
- Sex-Specific Results: Activating the loop increases mating involvement in females but reduces it in males.
- Behavioric Feedback: A feedback loop indicates that the cells both initiate and activate mating-related social relationships.
Rockefeller University is the cause.
The desire to reproduce in animals with social institutions is a complicated process that is controlled by the brain. It is influenced by both internal cues like hormones and external factors like interactions with prospective mates.
The prefrontal cortex ( PFC) is a region that has long been recognized to play a significant role. This node, which is located just behind the head, regulates numerous social behavior.
Analysts at Rockefeller University’s Laboratory of Molecular Biology, led by Nathaniel Heintz, have discovered how a province of the PFC influences the sexual drive in animals in a recent , paper , in , Cell , and in.
Cervical hormones and the “love estrogen” oxytocin both stimulate the loop, which connects to many layers of the mind.
Ines Ibaez-Tallon, research associate teacher in the laboratory and co-author of the study, claims that the circuit combines physiological states with the recognition of potential mates to arrange complex mental behaviors.
Interestingly, male mice also have this loop, but its activation causes them to become less interested in mating.
According to senior co-author Kun Li, a former Ph. D.,” This shared circuitry is flexibly sculpted by both hormonal state and biological sex to produce sex-specific patterns of social behavior.” Assistant professor in the School of Life Sciences at Tsinghua University is a PhD student in the facility.
It might help explain why cultural interest and physical motivation vary between sexes and across reproductive states.
Physical morphism in the head
The report builds on earlier laboratory findings. In the medial prefrontal cortex ( mPFC), the researchers named oxytocin receptor-expressing neurons ( OxtrINs ), a new type of brain cell that they named in 2014, OxtrINs.
Oxytocin is a hormone that is involved in all forms of bonding, whether it is interpersonal, loving, or social. The team discovered that the OxtrINs cerebral circuit in mice promoted receptivity to mating, but only in females and only during ovulation, or the rich period.
The researchers, led by Heintz and Ibaez-Tallon, conducted more studies to further confirm OxtrIN’s uneven influence, intrigued by the idea that a cell type that is similar in male and female mice may affect them very different.
In a 2016 study, it was discovered that adult mice experience less anxiety-related behavior when they are activated by OxtrINs but never female mice. Although it did not affect sexual mice’s levels of anxiety, it did, however, trigger the females to exhibit a higher social preference than adult mice.
Although both discoveries demonstrated a crucial function for the mPFC in adaptive social behaviors that are centered on sexual states, Li says that “how the mPFC senses internal physiological states and regulates versatile control over cultural behavioral outputs remained undetermined.”
The researchers wanted to go into those details for the current study, some of which were being conducted at Tsinghua University.
The circuit
In several layers of the mPFC, oxytocin-sensitive neurons had been discovered in the previous research. Layer 5, which transmits information to other brain regions, was the subject of the current study, according to Li and colleagues. In this layer, they discovered neurons that had the gene Cacna1h , which creates calcium channels, electrical switches that neurons use to communicate.
The anterior hypothalamic nucleus ( AHN) region of the hypothalamus, an ancient, hormonally driven region of the brain that regulates basic needs like hunger, thirst, and sleep as well as sexual behaviors, was then connected to it.
Then, using a variety of cutting-edge tools, they monitored female mice’s brains as they went through a full estrus cycle, the same as a human menstrual cycle, and engaged male mice in a variety of advanced techniques.
The Cacna1h+ neurons turned out to be very responsive to ovarian hormones, flashing up when the mice were fertile. The female mice also displayed increased sexual receptivity during this time, and they actively sought out and rejected male mice.
The team came to the conclusion that Cacna1h+ neurons are a hormonally influenced critical subset of neurons that respond to oxytocin prompts via OxtrINs, receiving social cues, and the AHN, which read internal signals, leading to sociosexual behavior.
However, manipulating the neurons caused the mice to behave in diametrically different ways. The female mice started acting as though they were hormonally ready to mate when Li activated the , Cacna1h , neurons during the nonfertile period. The mice lost all interest when she inhibited the neurons during estrus.
The male mice, whose brain activity was also monitored, had the opposite behavior. Female mice were more interested in female mice because they were more eager to try mating with them after slencing their Cacna1h+ neurons. And male sexual behaviors were slowed down by neurons activation.
The circuit appears to also have a feedback loop. That is, behavior can be initiated by Cacna1h+ neural activity as well as by the neurons themselves.
In estrus females, these neurons were highly activated by male stimuli and promoted sociosexual interest and receptivity, whereas in males these neurons did not respond to female stimuli, and the male mice displayed less interest.
Ibaez-Tallon calls it “funny.” The system can produce remarkably different functional outcomes even when the neural circuitry, neuronal populations, and molecular components are identical but differ only in terms of their levels of expression.
Although this study focused on ovarian hormones, research will be done into the relationship between testosterone and other disorders, which has long-established connections to depression, schizophrenia, anxiety, and other conditions.
It’s possible that testosterone plays a significant role in males ‘ development or responsiveness given the strikingly different functional roles Cacna1h+ neurons play, Li claims.
” This area of study may provide important insights into the social and emotional behavior’s sex-specific regulation and vulnerability.”
About this news from neuroscience research
Author: Katherine Fenz
Source: Rockefeller University
Contact: Katherine Fenz – Rockefeller University
Image: The image is credited to Neuroscience News
Original research: Free of charge.
Nathaniel Heintz and colleagues ‘” Reproductive states and social cues are incorporated into the regulation of sociosexual behavior.” Cells
Abstract
Reproductive states and social cues are incorporated into the regulation of sociosexual behavior.
Ovarian hormones are used to regulate female sociosexual behaviors and trigger them when appropriate social cues are present. They are essential for survival and reproduction.
Here, we identify primary estrous-sensitized Cacna1h+ medial prefrontal cortex neurons that integrate hormonal states with the recognition of potential mates to orchestrate these complex cognitive behaviors.
Through anterior hypothalamic outputs, mPFCCacna1h+ , neurons selectively modify mPFCCacna1h+ , neurons to shift sex-directed social behaviors between estrus and diestrus females. These neurons perform completely different tasks in males than those in females.
In distinct mPFCCacna1h+ , subpopulations, miniscope imaging reveals biased encoding of opposite-sex cues in estrus females and men. This is consistent with the depiction of self-estrous states and social target sex.
Mechanistically, ovarian-hormone-induced Cacna1h upregulation promotes T-type rebound excitation following oxytocin inhibition, causing estrus-specific activity changes and the sexually dimorphic function of mPFCCacna1h+ , neurons.
These findings reveal a prefrontal circuit that combines target-sex information with internal hormonal patterns to exercise top-down sexual control over adaptive social behaviors.
