动物实验 z-bo 2020-09-02 450

　　It is well known that both humans and animals rely on drugs such as cocaine and heroin and are addicted to drugs. Recent studies have shown that this drug addiction may be passed on to offspring.

　　This research was jointly completed by professors Ruki Umin and Marlan from the Institute of Brain Science and School of Basic Medicine, Fudan University. Studies have shown that the first and second generation puppies born after mice become addicted to cocaine are also more likely to become addicted to cocaine, and the addiction may be passed on to offspring. I will. The results of the study were published in Nature Communications on May 30.

　　The drug addiction of male mice was passed on to the male offspring of the Xiamen research team

　　Luma Min and Yambiao, other rats involved in the study were also injected with cocaine injection when they stepped on the pedals. The number of pedals required to allow the cocaine injection site to be continuously increased is a measure of the rat's desire for cocaine, which is to find drugs motivation. Since then, the researchers bred two groups of rats, namely the rats with the highest drug motivation (poisoned group) and female rats not exposed to cocaine, which produced offspring and their cocaine-dependent parents. Observe whether it affects future generations.

　　The final result shows that the behavior of the offspring of the dependent group is very different from that of the non-dependent group. The first-generation offspring of the addicted group had a "craving" for pedal cocaine, which was obviously stronger than the non-dependent group. .. Moreover, this strong cocaine addictive behavior can be observed in the second generation of offspring. Researchers also found that the inheritance of drug addiction requires mother mice to actively take cocaine, which is an acquired genetic feature. Therefore, the inheritance of drug addiction is not caused by changes in the genome level of the parent rat, but by changes in epigenetics, that is, genetic changes that can be inherited without changing the DNA sequence. possible. Ma Lan said in an interview with "China Science News": "Our research results show that the parental rat's drug use experience must be related to sperm DNA methylation, changes in epigenetic modification, and addicted populations. The appearance of independent groups of sperm The genetic changes are different: some methylation changes are retained in the offspring of the two groups of rats that have never been exposed to the drug. I am worried about the areas involved. Transcriptome analysis of brain cells also shows that the The expression of a series of genes related to plasticity has changed consistent with DNA methylation, but which genes are either methylated or changed in expression, leading to addictive crossover. Generation inheritance has not been studied."

　　This study investigated male rats and their male companions. Only select descendants. Further research is needed to determine whether female offspring of male rats become addicted to genetic drugs, and whether there is a difference in the likelihood of addiction between male and female adult offspring. The response of female animals to addictive drugs is more complex, such as menstrual cycles, changes in hormone levels, and other factors that affect the results of experiments. We use this offspring for research, but we have not yet compared gender differences in genetic drug addiction. "Dr. Ruki Kimin who participated in the study explained.

　　Cocaine has a major impact on brain structure and function

　　In fact, since humans began to be exposed to drugs, scientists have stopped studying drug addiction and its relationship with humans, especially the changes in brain structure. Not...

　　In 2013, a report published in "Natural Neuroscience" showed in experiments that soon after animals ingested cocaine, new structures related to learning and memory began to grow. The mice with the most brain changes have a higher preference for cocaine. Experts describe this situation as "learning poisoning" of the brain.

　　Researchers say that after taking cocaine, the structure of the brain changes within a few hours, which is the first step towards addiction.

　　In 2016, the Johns Hopkins University School of Medicine also conducted an experiment that the brain cells of rats ingesting high doses of cocaine may cause "uncontrolled autophagy" death, and pregnant rats are also exposed to cocaine. I found it suffered. Causes autophagy in fetal brain cells. In addition, the researchers concluded that targeted therapies to prevent brain cell suicide can prevent or reverse the side effects of cocaine. Similar research has never stopped." This kind of research has never stopped before other animal studies have shown that cocaine use affects the anxiety and depression levels, learning ability and drug sensitivity of offspring. Previous laboratory research has shown that cocaine, Heroin and other drugs can change the epigenetic changes in brain cells, which play an important role in the formation and long-term maintenance of addiction. I will achieve it."

　　Different from other studies, this is the first study of Ma Lan's research group. The first and second generation puppies that are produced after rats become addicted to cocaine are also addicted to cocaine. More likely. Her research results were selected as the research focus of "Asian Nature".

　　Ma told reporters: "The inheritance of addiction susceptibility depends on whether the animal is actively looking for drugs, not only on the dose of cocaine, but also on the motivation to seek the drug. Artificial injection of cocaine at the same dose as the addicted rats Their addictive behavior is similar to that of the non-addictive group. It is not due to mutations at the genome level, but because of acquired genetic traits, triggered by a high motivation to find drugs."

　　Venus.

　　Director of the Institute of Brain Science, Fudan University, Director of the Pharmacology Center of the School of Basic Medicine, genetic research is underway, "formation and elimination of memories of psychoactive substance poisoning, the chief scientist of the National "973 Program"," led by Malan The research team has focused on drug addiction research for 20 years, focusing on the neural circuits and molecular basis of drug addiction-related memories, as well as the mechanism of memory formation and death. In these studies, Ma Lan led a team to discover the role of G protein-coupled receptor kinases in synaptic plasticity and dependent memory, and adrenaline-biased signaling pathways regulate the consolidation of cocaine memory. The research team also studied the epigenetic regulation of drug addiction. Mechanisms such as small RNA and histone acetylation play an important role in drug-seeking behavior and motivation. I found.

　　"Research on the genetic aspects of addiction is ongoing. We are currently experimenting with other addiction drugs in animal models to further study the mechanism by which addiction increases the risk of addiction in offspring. We will do it." Ma Lan said .