Nature Methods: gender influences the antidepressant effect of ketamine?

The results of a study in mice using ketamine, an antidepressant, may vary depending on the sex of the researchers What is ketamine? Ketamine is mainly used as surgical anesthetic in clinic In addition, ketamine is a drug However, recent studies have provided more evidence that ketamine is a safe, rapid and effective drug for the treatment of depression, which can produce ideal antidepressant effect in a few hours However, the mechanism of ketamine in the treatment of depression has not been studied clearly Therefore, many researchers try to use animal model tests to infer its mechanism, so as to fully understand the potential and limitations of ketamine in antidepressant One of them is Professor polymenia Georgiou, a neuroscientist at the University of Maryland, Baltimore In 2015, a male colleague asked her to help him do some experiments while he was away, including a standard method for testing antidepressants, called the forced swimming test In this study, the researchers injected healthy mice with a drug, and then placed them in a limited water tank, in which the mice struggled desperately to escape but could not escape, thus providing an unavoidable oppressive environment After a period of experiment, the mice showed a typical "immobility", reflecting a kind of "behavior absolute" State of hope ", recording the time spent by the mice in this environment to produce a desperate immobility state A male colleague of Professor Georgiou, from Google, found that ketamine had antidepressant effects Mice that had been injected with ketamine had a longer swimming time, and mice that had not been injected with ketamine were soon in despair and gave up swimming Smell and brain although professor Georgiou strictly followed his male colleagues' scientific experiment plan, she found that the swimming time of mice injected with ketamine did not extend at all When she and three female and four male researchers tried to find out why there was such a difference, they found that ketamine had an antidepressant effect only when the male researchers did the experiment So the researchers suspected it was the smell, and put the mice in a fume hood so they couldn't hear who was injecting ketamine Results the antidepressant effect of ketamine was not observed at all, regardless of the sex of the experimenter The antidepressant effect of ketamine reappeared after the researchers placed a man's T-shirt next to a mouse in a fume hood This suggests that the smell of men is essential for ketamine to play an antidepressant role Professor Todd Gould, a neuroscientist in the head who led professor Georgiou's research team, saw this result and repeated professor Georgiou's forced swimming test: eight male and eight female researchers injected mice with ketamine respectively, and they saw the same result: the mice injected by women did not respond to the drug Researchers repeatedly tested other antidepressants, but found that gender did not affect the effectiveness of other antidepressants Therefore, the researchers speculated that the antidepressant effect was the result of the interaction between ketamine and male odor in the mouse brain Adrienne Betz, a neuroscientist at the University of Quinnipiac, said: "although the results are fascinating, I have to warn you The results are still preliminary It is not clear whether this effect has a specific effect on ketamine and mice " Lisa Monteggia, a neuroscientist at the University of Texas in the US, doesn't agree with other potential effects "Other factors, such as whether researchers are under pressure when injecting mice, may affect their behavior," said Lisa Monteggia Professor Gould and Professor Georgiou agree that their findings are not necessarily invalid At least in their lab, ketamine produced antidepressant effects only when men injected mice with ketamine Professor Gould also suspects that the gender of patients taking ketamine may also affect the effectiveness of antidepressants, but no tests have been conducted Thesis link: https://