Pubdate: 17 Dec 1998 Source: Reuters Copyright: 1998 Reuters Limited. U.S. STUDY SHOWS MARIJUANA CAN AFFECT FERTILITY WASHINGTON, Dec 16 (Reuters) - Scientists said Wednesday they had shown how active ingredients in marijuana can affect fertility by damaging sperm function. They said natural body compounds known as anandamides, which are similar to compounds found in marijuana, may be important for helping sperm get to and fertilize an egg. Cannabinoids in marijuana are similar enough to anandamides to confuse the body and interfere with this, they said. Herbert Schuel and colleagues at the University of Buffalo in New York said human sperm contain receptors, a kind of chemical doorway, that the active ingredients in cannabis can use. "We've known for 30 years that very heavy marijuana smoking has a drastic effect on sperm production within the testis, which can lead to higher rates of infertility," Schuel said in a statement. "Our new findings suggest that anandamides and THC in marijuana smoke may also affect sperm functions required for fertilization in the female reproductive tract." Anandamides are neurotransmitters, or message-carrying chemicals. It has been known for years that the cannabinoids, the active ingredients, in marijuana are similar enough to anandamides to use the same chemical doorways into brain cells. Schuel's group found that sperm also carry receptors for anandamides, and that cannabinoids will attach themselves to these receptors given a chance. Reporting to a meeting of the American Society of Cell Biology in San Francisco, Schuel's group said the cannabinoids interfered with the release of enzymes the sperm need to penetrate an egg, with the regulation of sperm swimming and with the binding of a sperm to the outside of an egg. Evidently, he said, when people use marijuana heavily the body becomes flooded with cannabinoids and normal functions that use the similar anandamide chemicals are overwhelmed. - --- Checked-by: Mike Gogulski