Lack of CRH Affects the Behavior but Does Not Affectthe Formation of Short-Term Memory

Abstract Corticotropin-releasing hormone (CRH) isinvolved in modification of synaptic transmission andaffects spatial discrimination learning, i.e., affects theformation of memory in long-term aspect. Therefore, wehave focused on CRH effect on short-term memory. Wehave used stress task avoidance (maze containing threezones: entrance, aversive, and neutral) and compared thebehavior and short-term memory in wild-type mice andmice lacking CRH (CRH KO) experiencing one 120-minsession of restraint stress. As control, non-stressed animalswere used. As expected, the animals that experienced thestress situation tend to spend less time in the zone in whichthe restraint chamber was present. The animals spent moretime in the neutral zone. There were significant differencesin number of freezing bouts in the aversive and entrancezones in CRH KO animals. CRH KO control animalsentered the neutral zone much more faster than WT controland spent more time immobile in the neutral zone than WTcontrol. These data give evidence that lacking of CRHitself improves the ability of mice to escape away frompotentially dangerous area (i.e., those in which the scent ofstressed animal is present).Keywords CRH Restraint stress Post-stress period Stress task avoidance Working memor