title: Effects of lead exposure on dendrite and spine development in hippocampal dentate gyrus areas of rats.
abstract: Lead exposure has been implicated in the impairment of synaptic plasticity in the hippocampal dentate gyrus (DG) areas of rats. However, whether the degradation of physiological properties is based on the morphological alteration of granule neurons in DG areas remains elusive. Here, we examined the dendritic branch extension and spine formation of granule neurons after lead exposure during development in rats. Dendritic morphology was studied using Golgi-Cox stain method, which was followed by Sholl analysis at postnatal days 14 and 21. Our results indicated that, for both ages, lead exposure significantly decreased the total dendritic length and spine density of granule neurons in the DG of the rat hippocampus. Further branch order analysis revealed that the decrease of dendritic length was observed only at the second branch order. Moreover, there were obvious deficits in the proportion and size of mushroom-type spines. These deficits in spine formation and maturity were accompanied by a decrease in Arc/Arg3.1 expression. Our present findings are the first to show that developmental lead exposure disturbs branch and spine formation in hippocampal DG areas. Arc/Arg3.1 may have a critical role in the disruption of neuronal morphology and synaptic plasticity in lead-exposed rats.
authors.affiliation: School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China.
authors.forename: Fan
authors.initials: F
authors.lastname: Hu
authors.affiliation: School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China.
authors.forename: Meng-Meng
authors.initials: MM
authors.lastname: Ge
authors.affiliation: School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, 230027, People's Republic of China.
authors.forename: Wei-Heng
authors.initials: WH
authors.lastname: Chen
mesh_terms: D000818:Animals; D015153:Blotting, Western; D003598:Cytoskeletal Proteins / Q000378:metabolism; D003712:Dendrites / Q000187:drug effects / Q000473:pathology* / Q000502:physiology; D018891:Dentate Gyrus / Q000187:drug effects / Q000254:growth & development / Q000473:pathology* / Q000503:physiopathology; D004195:Disease Models, Animal; D007854:Lead / Q000633:toxicity; D020263:Lead Poisoning, Nervous System / Q000473:pathology* / Q000503:physiopathology; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology; D011897:Random Allocation; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D013569:Synapses / Q000187:drug effects / Q000473:pathology / Q000502:physiology
chemical_list: D003598:Cytoskeletal Proteins; D009419:Nerve Tissue Proteins; C092069:activity regulated cytoskeletal-associated protein; D007854:Lead
keywords: Arc/Arg3.1; Golgi-Cox; hippocampal dentate gyrus (DG) areas; lead; spine