Apples for Health- Happiness hormone needed for mothers

Happiness hormone needed for mothers

BERLIN, June 24 (UPI) -- Lack of the "happiness hormone" serotonin in the brain causes impaired maternal behavior in mice, researchers in Germany said.

Researchers Dr. Natalia Alenina, Dana Kikic and Michael Bader of the Max Delbruck Center for Molecular Medicine Berlin-Buch said that they also found that the presence of serotonin in the brain is not crucial for the survival of the animals.

Furthermore, the researchers were able to confirm that there are two strictly separate pathways of serotonin production -- one gene is responsible for the formation of serotonin in the brain, another gene for the production of the hormone in the body.

The researchers "switched off" the gene Tph2 in mice to elucidate the function of the gene in the brain. Tph2 produces the enzyme tryptophan hydroxylase, which is responsible for the formation of serotonin.

After the researchers switched off Tph2, the animals produced almost no serotonin in the brain. Nevertheless, the animals were viable and half of them survived until adulthood. However, they needed more sleep during the day and the regulation of their respiration, body temperature and blood pressure was altered.

The study, published in the Proceedings of the National Academy of Sciences, found the female mice were able to give birth and produced enough milk to feed their pups, but their impaired maternal behavior led to poor survival of the offspring.