2型糖尿病鼠胰腺β细胞中SERCA泵的变化对钙振荡波形影响的建模研究

Modeling Study on Ca^(2+) Waves Based on Changes of SERCA Pump in Pancreaticβ-Cells of TypeⅡDiabetic Rats

在原内质网Ca^(2+)-ATP酶(SERCA)模型的基础上建立了2型糖尿病鼠胰腺β细胞的SERCA模型,并将两模型分别应用于钙振荡模型里来模拟SERCA泵的变化对胞质钙浓度([Ca^(2+)])的影响.分析结果发现:(1)病鼠胰腺β细胞中的[Ca^(2+)]升高,并且钙振荡周期和幅值增大;(2)细胞中ATP浓度([ATP])降低,ATP振荡周期增大,但幅值变化不明显;(3)内质网(ER)中钙振荡波形的周期增大,幅值减小.结论:在2型糖尿病鼠胰腺β细胞中,其[Ca^(2+)]相对于正常大鼠明显升高的现象与细胞中SERCA泵转运钙的能力下降有关.

The model of the sarco-endoplasmic reticulum Ca^2＋-ATPase （SERCA） pump in pancreaticβ-cells of typeⅡdiabetic rats was built based on the original SERCA pump model. The two kinds of SERCA pump models were integrated into a model of calcium oscillations and the effect of the change of SERCA pumps on the cytosolic calcium concentration （[Ca^2＋]） was simulated. The results showed that： （1） the [Ca^2＋] in deseasedβ-cells increased accompanying increase of the period and the amplitude of cytosolic calcium oscillations, （2） the cytosolic adenosine triphosphate（ATP） concentration （[ATP]） decreased and the period of ATP oscillations increased, but no significant alteration of in amplitude is noticed, （3） the period of calcium oscillations in the endoplasmic reticulum（ER） increased, but the amplitude decreased. In conclusion,this modeling demonstates that [Ca^2＋] in pancreaticβ-cells of typeⅡdiabetic rats is usually higher than that of the normal rats, which is related to the reduced transit capacity of SERCA pumps.