Effects of subcutaneous injection of recombinant human growth hormone on ability of learning, memory, and spatial exploration of rats with vascular dementia
YIN Jiazhen
LI Beihua
LI Guochun
ZHANG Hong
HUANG Xinwu
Abstract：Objective To observe the effects of recombinant human growth hormone (rhGH) on the ability of learning,memory and space exploration of rats with vascular dementia (VD) and to explore its possible mechanism.Methods Forty-five rats were randomly divided into three groups:the experimental group,model group,and normal group,with 15 rats in each.The VD model was prepared in the experimental group and the model group through bilateral carotid artery ligation at different time points (we ligated the right carotid artery three days after the left carotid artery was ligated).The normal group used the same method to separate the bilateral carotid arteries,but we did not ligate the common carotid artery.At the beginning of the first day after modeling,rhGH (0.2 IU/100 g) was injected into the neck of the rats in the experimental group,while rats of the normal group and model group were given the same amount of normal sodium once a day for 28 days.Water maze test was used to assess the ability of learning and memory and space exploration of rats.ELISA was used to detect the levels of vascular endothelial growth factor (VEGF),insulin-like growth factor 1 (IGF-1) and growth hormone (GH) in the serum,cortex,and hippocampus.TUNEL apoptosis staining was used to observe the status of neuronal apoptosis (IOD value).Results Compared with the normal group,the experimental group from the first to the fourth day and the model group from the first to the sixth day had longer escape latency (P ＜ 0.05).Compared with the model group,the experimental group had shorter escape latency on the 2nd,4th,5th,and 6th days (P ＜0.05).Compared with the model group,the experimental group and the normal group passed the platforms more (P ＜ 0.05).Compared with model group,the levels of VEGF,IGF-1,and GH in the serum,cortex,and hippocampus of the experimental group increased (all P ＜ 0.05).Compared with the normal group,the levels of VEGF,IGF-1,and GH in the serum,cortex,and hippocampus of the model group decreased (all P ＜ 0.05).Compared with the model group,the IOD value of TUNEL apoptosis staining in the hippocampus of the experimental group and the normal group decreased (P ＜ 0.05).Conclusion The rhGH can improve the ability of learning,memory,and space exploration in VD rats by increasing the VEGF and IGF-1 levels in the serum,cortex,and hippocampus.
Keywords：vascular dementiarecombinant human growth hormonevascular endothelial growth factorinsulin-like growth factor
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：4( 24-27 )