Brain Chemicals Control Sexual Behavior in Mice

A recent study published in Neuron on March 19, 2025, explores how the interaction between dopamine and acetylcholine in the brain influences sexual behavior in male mice. This research sheds light on the complex brain processes involved in the progression of sexual behavior, from mounting to ejaculation, and may pave the way for treatments targeting sexual dysfunctions, such as premature ejaculation.

Understanding the brain's role in sexual behavior

Sexual behavior in animals is a complex series of actions, ranging from mounting to ejaculation. While previous studies have primarily focused on the initiation of sexual behavior, the brain's activity during other stages of the process, such as mounting, intromission (penis insertion) and ejaculation, remained unclear. To bridge this gap, researchers at the National Institute of Biological Sciences in Beijing, led by Qinghua Liu, investigated brain activity in male mice at each phase of sexual activity.

How dopamine and acetylcholine influence sexual progression

The team focused on the nucleus accumbens, a brain region associated with reward processing. They studied the release of two key neurotransmitters: dopamine, which is linked to pleasure, and acetylcholine, which regulates dopamine release. Using fluorescent sensors, the researchers monitored neurotransmitter activity in male mice’s brains during sex.

“We are able to look at these events at a very fine time resolution to understand how neurotransmitters interact with each other.”

Dr. Ai Miyasaka.

Before mounting, acetylcholine was released rhythmically. Approximately six seconds later, dopamine release followed. As the mice engaged in intromission, the release of both chemicals fluctuated rhythmically in sync with their thrusting movements. In mice that reached ejaculation, dopamine release decreased before rising sharply during the transition from intromission to ejaculation.

Dopamine receptors regulate sexual behavior

The study also revealed the role of dopamine receptors in regulating the correct sequence of sexual behavior. The researchers discovered that nerve cells expressing two dopamine receptors, D1R and D2R, were less active than usual during intromission. When D1R cells were activated artificially, the mice returned to the mounting stage. Conversely, activating D2R cells halted sexual activity altogether. These findings highlight the precise dopamine signaling needed to ensure sexual behavior follows the correct progression.

Potential implications for sexual dysfunction treatments

Although the research was conducted in mice, the authors suggest that similar brain regions and neurotransmitter systems might play a role in human sexual function. They propose that these findings could provide valuable insights into developing treatments for sexual dysfunction, especially premature ejaculation, which affects 20-30% of sexually active men.

“Now we have a precise understanding of how dopamine works during sex and ejaculation. So, I believe our study has opened the door to the development of clinical treatments.”  

Dr. Ai Miyasaka.

Conclusion: Insights into sexual behavior and potential therapies

This study offers a detailed examination of how dopamine and acetylcholine work together to regulate male sexual behavior in mice. By understanding these brain mechanisms, researchers hope to inform the development of clinical treatments for sexual disorders such as premature ejaculation.

Reference: Miyasaka A, Kanda T, Nonaka N, et al. Sequential transitions of male sexual behaviors driven by dual acetylcholine-dopamine dynamics. Neuron. doi: 10.1016/j.neuron.2025.01.032

This article has been republished from the following materials. Note: material may have been edited for length and content. For further information, please contact the cited source. Our press release publishing policy can be accessed here.

This content includes text that has been generated with the assistance of AI. Technology Networks' AI policy can be found here.