The Effect Of Pups Company On Conditioned Fear In Postpartum Rats And The Influence Of Conditional Fear On Maternal Behavior

Fear conditioning is a paradigm for the study of fear acquisition,consolidation,extinction,retrival and reconsolidation,as well as the neural mechanisms underlying these processes.In the early twentieth Century,Pavlov discovered classical conditioned fear.Up to now,substantial studies have focused on the conditioned fear,as such we have a deeper understanding of the mechanism of conditioned fear.Many factors influence the distinctive stage of conditional fear.For example,cognitive factors and hormone factors affect the different stage of conditioned fear in human.For rats,various drugs,different programs and companion companions can also affect the performance of their fear of conditions.Rats are the most used experimental animal for the study of conditional fear.The male,female rats,adolescent rats,adult rats showed on condition of fear,but few studies have involved in conditioned fear in the the postpartum female rats.Only one study of Rick Bashir has shown postpartum female rats with pups exhibited less fear to conditioned tones than animals without pups,suggesting maternal behavior contributes to reduce fear response.Since maternal behavior can affect conditional fear,does conditional fear in turn affect maternal behavior? However,the present study involves only the stage of maternal postpartum rats with expression of conditioned fear.We conducted the studies that concerned the effect of maternal behavior on acquisition,retrieval,and reconsolidation of conditioned fear.Methods: Cue-induced delay fear conditioning paradigm was used in the present paper to study the effect of maternal behavior on distinctive stage of fear conditioning..Then compared with female rats with postpartum and sham rats with groups of postpartum mothers in the acquisition and expression of conditioned fear,extinction and reconsolidation,the four different stages of different manifestations of fear.And in the establishment of fear,were given postpartum white noise stimulation,whether the maternal behavior of female mice in the rat cage change.Results: 1.Postpartum female rats with pups exhibited less fear to tones than that without pups,or with artificial pups;2.The results showed that pup company can significantly affected the performance of postpartum in the acquisition of fear and reduce the freezing of dam significantly in the expression part but did not affect remarkably on extinction;the monotone had no influence on maternal behavior between experimental group and control group which was a evidence that indicated the positive role of maternal behavior when faced with fear;3.In the reconsolidation process,the mother rats with pups produced less freezing in the fear test than rats without pups;4.Maternal behavior was not impaired by conditioned fear,whereas maternal fear reduced conditioned fear response.Conclusion: Rats with had a positive effect on postpartum maternal conditions in each stage except outside the fear extinction,and can help postpartum mothers actively face conditions of fear.