Document Type : Research Paper

Authors

Abstract

Thus the aim of the current study was to determine whether intraperitoneal (i.p.) administration of insulin improves the water maze motor performance of the rats. Forty male wistar rats were randomly assigned to for groups (each 10 rats). Insulin was injected (0, 1, 6, and 12 U/Kg) once daily for one week. Animals training and testing were conducted using the Morris water maze. Data analyzed using split plot ANOVA (SPANOVA). Results showed significant main effect of time for distance and escape latency in acquisition stage (P<0.001). Also, intraperitoneal injection of insulin, without any significant effect on serum glucose levels, significantly reduced distance moved (P<0.001) and escape latency (P=0.004). Moreover, in retention test, insulin reduced escape latency to hidden platform in a dose dependent manner (dose 12 & 1 U/Kg). Therefore, peripheral administration of insulin has central effects and can enhance motor performance via improvement of spatial learning and memory. 

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