Effect of intraperitoneal or intracerebroventricular injection of streptozotocin on learning and memory in mice

Yang Zhang; Rong Ding; Shanshan Wang; Zhiyun Ren; Lingyan Xu; Xunle Zhang; Jiahui Zhao; Yu Ding; Yu Wu; Yuesong Gong

doi:10.3892/etm.2018.6487

Effect of intraperitoneal or intracerebroventricular injection of streptozotocin on learning and memory in mice

Exp Ther Med. 2018 Sep;16(3):2375-2380. doi: 10.3892/etm.2018.6487. Epub 2018 Jul 19.

Authors

Yang Zhang^{1

2}, Rong Ding¹, Shanshan Wang¹, Zhiyun Ren¹, Lingyan Xu¹, Xunle Zhang¹, Jiahui Zhao¹, Yu Ding¹, Yu Wu³, Yuesong Gong¹

Affiliations

¹ Jiangsu Key Laboratory of Therapeutic Material of Chinese Medicine, Department of Biopharmaceutics and Food Science, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, P.R. China.
² Department of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu 221004, P.R. China.
³ Department of Nephrology, The First People's Hospital of Xuzhou, Xuzhou, Jiangsu 221002, P.R. China.

Abstract

Alteration of behavior and PSD proteins in cerebral cortex and hippocampal synaptosome in the Alzheimer's disease (AD) mouse model were determined. AD was established by intraperitoneal injection of streptozotocin (STZ) in neonatal mice (intraperitoneal AD group) or intracerebroventricular injection of STZ in adult mice (intracerebroventricular AD group). Body weight and blood sugar level were measured. Following Morris water maze (MWM) test and fear-conditioning test, cerebral cortex and hippocampus tissues were collected and the levels of PSD95 and shank3 proteins in these tissues were measured by western blot analysis. The body weight was reduced and the blood sugar concentration was increased in the intraperitoneal AD group compared with the control group. In contrast, the body weight was reduced, while the blood sugar concentration was not increased in the intracerebroventricular AD group compared with the control group. Escape latency in both AD groups was extended compared with the control group. The freezing time in the intraperitoneal AD group was increased, while in the intracerebroventricular AD group, the freezing time was reduced. PSD95 and shank3 proteins in the cerebral cortex in both AD groups were decreased compared with the control group. PSD95 in the hippocampus was reduced in both AD groups compared with the control group. Shank3 in the hippocampus in the intracerebroventricular AD group was significantly reduced compared with the control group. Intraperitoneal injection of STZ in neonatal mice led to elevated blood sugar, impaired spatial memory and enhanced emotional memory when they become adults. In contrast, intracerebroventricular injection of STZ in adults directly led to deteriorated spatial and emotional memory without alteration of blood sugar content, which could be associated with the changes of PSD95 and shank3 proteins in hippocampus.

Keywords: Alzheimer's disease mouse model; intracerebroventricular injection; intraperitoneal injection; learning and memory; postsynaptic density; shank protein; streptozotocin.