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Common herbicide disrupts ovulation
The common and highly-used herbicide atrazine can act within the brain to disrupt the cascade of hormone signals needed to initiate ovulation, finds a study with rats published online in the journal Biology of Reproduction.
Ovulation is a complex process that begins in the brain and ends with the release of eggs from the ovary. This new study finds that exposure to atrazine can interrupt this process but once the exposure ends, normal function resumes in a few days. The results shed new light on the way atrazine affects the female reproductive system and the persistence of these effects when adults are exposed.
The study used rats whose ovaries were surgically removed. The female rats were given the hormones estrogen and progesterone to stimulate the release of two important hormones needed for ovulation: gonadotropin releasing hormone (GnRH) from the brain and luteinizing hormone (LH) from the pituitary gland.
The rats were then fed atrazine daily for four days to see if the herbicide could interfere with the release of GnRH and LH. The doses were higher than would be considered relevant for humans but are within the range of what previous studies have used in similar animal studies. Doses given were 0, 50, 100 or 200 milligrams per kilogram (mg/kg) of body weight.