L型和P／Q型钙通道对大鼠胰岛β细胞胰岛素双相分泌的调控  

Regulatory role of L-type and P/Q-type calcium channels in biphasic insulin secretion of rat islet cell

作　　者：孙富军[1] 李代清[1] 张秋梅[1] 

机构地区：[1]天津医科大学代谢病医院,内分泌研究所卫生部激素与发育重点实验室,300070

出　　处：《中华糖尿病杂志》2012年第10期630-634,共5页CHINESE JOURNAL OF DIABETES MELLITUS

基　　金：国际糖尿病研究协会中欧合作基金（EFSD,2600）;天津市重大科技攻关项目（09zczDsFI）4500）;天津市应用基础及前沿技术研究计划重点项目（08JczDJc25100）

摘　　要：目的通过胰腺原位灌注实验结合钙通道阻断剂的应用探讨L型和P／Q型钙通道在调控大鼠胰岛B细胞胰岛素分泌中的作用。方法健康雄性sD大鼠24只，采用随机数字表法分为对照组（n=8）、L型通道阻断组（n=8）和P／Q型通道阻断组（n=8）。用戊巴比妥钠对大鼠进行腹腔注射麻醉，沿腹正中线做一切口，将胰腺与脾、胃、结肠等组织器官分离，分别在腹主动脉和门静脉上适当的位置插入硅胶导管。各组大鼠均先用37℃改良三羧酸循环4一羟乙基哌嗪乙磺酸缓冲液（modifiedKrebs—RingerHEPES）通过腹主动脉插管以1ml／min流速预灌注40min，随后开始正式灌注实验并收集门静脉插管的流出液。对照组先用含3．3mmol／L葡萄糖的ModifiedKrebs—RingerHEPES低糖缓冲液对完整的大鼠胰腺灌注10min，再用含16．7mmol／L葡萄糖的ModifiedKrebs—Ringer HEPES高糖缓冲液灌注25min；L型通道阻断组先用低糖灌注液灌注10min，再用50mnol／L依拉地平一高糖灌注液灌注25rain；P／Q型通道阻断组用低糖灌注液灌注10min，再用10nmol／L漏斗网蛛毒素一高糖灌注液灌注25min。各组均从门静脉收集每分钟的流m液，用放射免疫分析法检测其胰岛素水平。以第1～10分钟为低糖灌注液灌注期，第11～15分钟为第1时相，第16～35分钟为第2时相，计算胰岛素分泌率。多组数据比较采用单因素方差分析，进一步两两比较采用SNK．q检验。结果对照组、L型通道阻断组和P／Q型通道阻断组大鼠的体重、空腹血糖值比较差异均无统计学意义（F值分别为1．224、0．377，均P〉0．05）。大鼠基础胰岛素分泌率各组间比较差异均无统计学意义（F=0．095，P〉0．05）。高糖刺激下，L型通道阻断组的胰岛素1相和2相分泌率及分泌峰值均显著低于对照组和P／Q型通道阻断组[分别为（402±24）、（744±32）、（728±42）~U／min，F=163．879，P�Objective To study the role of L-type and P/Q-type calcium channels in insulin secretion of rat islet 13 cell. Methods Healthy SD rats were randomly divided into control group （ n = 8 ） , L-type channel blocking group （ n = 8） and P/Q-type channel blocking group （ n = 8 ）. Sodium pentobarbital was injected into abdominal cavity of the rat. Then a slice was made in its abdomen and separated the pancreas from spleen, stomach, colon and other organs. Finally the silicone catheters were inserted into the abdominal aorta and portal vein on the proper position. The pancreas of rats of the three groups were first perfused with 3.3 mmol/L glucose solution for 10 minutes and then with 16. 7 mmol/L glucose solution for 25 minutes. The glucose solution for L-type channel blocking group and P/Q-type channel blocking group contains 50 nmo]/L isradipine and 10 nmol/Leo-Agatoxin IVA respectively. Collect the fluid from the portal vein per minute to detect the insulin level by radioimmunoassay. Using SPSS-statistical software package, the experimental data were analyzed through the method of Student Newman Keuls of One-Way-ANOVA. Results The fasting blood glucose and body weight were no significant difference among three groups （ F = 0. 377,1. 224 ,P 〉 0. 05 ）. The basal insulin secretion rates were no significant difference among three groups （F = 0. 095, P 〉 0. 05 ）. Glucose-evoked insulin secretion rate of the first phase and the second phase, secretion peak value of insulin in L-type channel blocking group were significantly lower than those in the control group respectively[ （402 _＋24） vs （744 _＋32） vs （728 _＋42） ixU/min,F = 163. 879 ,P 〈0. 01 ; （323 ~ ＋29） vs（568 _＋40） vs （563 _＋ 19） IxU/min,F = 95. 043 ,P 〈0. 01 ;（521 _＋43） vs（ 1134 _＋ 146） vs （ 1083 _＋ 199） txU/min, F = 27. 713, P 〈 0. 01 ]. Glucose-evoked insulin secretion rate of the first phase and the second phase, secretion peak value of insulin were no significantly differences bet

关 键 词：胰岛Β细胞 钙通道 胰岛素 

分 类 号：R363[医药卫生—病理学]