Syntaxin4 and Synapsin3 mRNA Levels Induced by Long-Term Iron Toxicity in Rat (Rattus norvegicus)

Öz

Although iron is necessary for brain tissue, its overload causes many metabolic disorders as well
as neurodegenerative disorders. Syntaxin4 and synapsin3 are proteins associated with synaptic vesicles that play
a role in neurotransmitter release. In this study we investigated the effects of sublethal doses of ferric iron at 0.87
ppm, 3 ppm, 30 ppm and 300 ppm on mRNA levels of genes coding syntaxin4 and synapsin3 proteins that function
in nerve cell signal transmission in cortex and hippocampus tissues of rats (Rattus norvegicus). While mRNA level
of the syntaxin4 gene was unchanged in the cortex, mRNA level of syntaxin4 decreased with 30 ppm and 300 ppm
exposure in the hippocampus. mRNA level of synapsin3 gene in both cortex and hippocampus tissues increased in
all treatment groups compared to control group.

Anahtar Kelimeler

• Iron overload,mRNA expression,syntaxin4,synapsin3

Sıçan (Rattus norvegicus)’da Uzun Süreli Demir Toksisitesi ile Uyarılan Sintaksin4 ve Sinapsin3 mRNA Seviyeleri

Öz

Demir beyin dokusu için gerekli olmasına rağmen aşırı birikimi nörodejeneratif rahatsızlıkların yanında
birçok metabolik bozukluklara neden olmaktadır. Sintaksin4 ve sinapsin3 nörotransmitter salınımında rol oynayan
sinaptik veziküller ile ilişkili proteinlerdir. Biz bu çalışmada ferrik demirin (Fe3+) 0.87 ppm, 3 ppm, 30 ppm ve 300
ppm subletal dozlarına maruz kalmış sıçanların (Rattus norvegicus) korteks ve hipokampus dokularındaki sinir
hücre sinyal iletiminde fonksiyonu olan Sintaksin4 ve Synapsin3 proteinlerini kodlayan genlerin mRNA seviyeleri
üzerine etkilerini araştırdık. Sintaksin4 geninin mRNA seviyesi korteks dokusunda değişmez iken hipokampus
dokusunda 30 ppm ve 300 ppm maruziyeti ile mRNA seviyesi azalmıştır. Hem korteks hem de hipokampus
dokularında sinapsin3 geni mRNA seviyesi artmıştır.

Anahtar Kelimeler

• Demir birikimi,mRNA ifadesi,sintaksin4,sinapsin3

Kaynakça

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