The present invention relates to a sleep-inducing preparation comprising a prostaglandin derivative as an effective ingredient.
Since prostaglandin (hereinafter referred to as xe2x80x9cPGxe2x80x9d) exhibits various important physiological actions in a trace amount, the syntheses of the derivatives from natural PGs and the biological activities have been investigated with the intention of a practical use as medicines and have been reported in many literatures.
Particularly, PGs have been reported on the various central nervous actions and have been clarified as to the intracerebral content, biosynthesis, metabolic pathway, their intracerebral localizations and changes with growth or aging, and there has been taken an interest in the relation of PGs with sleep and wake. Among them, PGD2 has been known as an intracerebral humoral factor which controls the occurrence or maintenance of sleep,one method or the other. Survival and success rates were similar — about 4 percent of each group died or had a heart attack, stroke or major bleeding in the following month.

"The more you do the better you get," and the better patients fare, said the study's leader, Dr. Sanjit Jolly of McMaster University in Hamilton, Ontario.

The study was funded by the Canadian government, a Canadian nonprofit, and Sanofi-Aventis SA and Bristol-Myers Squibb Co. (It was part of a larger study testing different doses of an anti-clotting drug used after angioplasty.) Results were published online by the journal Lancet.

The cardiology college's president, Dr. Ralph Brindis, said the study should be "a tipping point" to boost the arm method in the U.S.

"Every study that's ever been done shows it's