Scientists discover the keys that can cause bipolar mood swings

Researchers at McGill University Bipolar disorder Research: Understand the causes of shifts between manic and depressed states.

The normal adult sleep-wake rhythm is usually 24 hours apart, and the 48 hours awake cycle is Reported in patients with bipolar disorder. These sleep cycles are usually consistent with mood states and are associated with shorter sleep days Mania Long sleep days related to depression.

in Research published in Advances in scienceMcGill scientists reported that mood fluctuations that occur regularly in patients with bipolar disorder are driven by two internal “clocks.” One is a sleep awake clock, and the second is a driving clock Dopamine– Usually produces neurons that affect arousal. A second dopamine-based clock is thought to remain dormant in healthy people, but people with bipolar disorder may shift between man’s disease or depressed states, depending on how these two clocks line up over time.

In this study, the second clock was activated in mice to create a behavioral rhythm similar to mood fluctuations in bipolar disorder. When reward-centered dopamine-producing neurons in the brain are destroyed, behavioral rhythms halt, indicating that these dopamine neurons are important factors in the swelling of the bipolar mood.

Specifically, mice were administered methamphetamine-containing water to develop motor rhythms with periods of 48 hours or more and behaviors associated with man’s disease status. This cycle was abolished by destroying or destroying dopamine-producing neurons in the ventral compression region (VTA) or by destroying projects into the nucleus accumbens (NAC). The activation of these same neurons resulted in prolonged motor periods that were counteracted by antipsychotic treatment. That’s what VTA and NAC are The key parts of the brain’s motivation and reward systemand together they form an important circuit known as the mesopathetic pathway.

“Our model provides the first universal mechanism of mood switching or cycling, which behaves similarly to the sun and moon driving spring currents at certain repetitive times.” The lead author, Dr. Kai Florian Stouch, saidAssociate Professor in McGill’s Department Psychiatry.

Current treatments for bipolar disorder focus on mood stabilization, but often do not address the root causes of mood fluctuations. “The discovery of dopamine-based awakening rhythm generators provides a novel and clear target for treatment. It should aim to modify or silence this watch to reduce the frequency and intensity of mood episodes,” Dr. Storch said.

The specific molecular tasks of dopamine clocks remain unknown. The researchers will continue to investigate the physiological mechanisms of dopamine clocks and the genetic and environmental factors that may activate this clock in humans.