目的：研究胆汁α淀粉酶保存时间及离心速度改变时活力变化,探讨影响胆汁α淀粉酶稳定性的因素。方法：收集大连医科大学附属第一医院普外三科行内镜逆行胰胆管造影术病人27例。18例通过碘-淀粉比色法,测定胆汁样本于4 ℃保存30 min、3 h、12 h、24 h、72 h和30 d后6组α淀粉酶的活力。9例样本分别以不离心、3 000 r/min和8 000 r/min速度离心,测定3组α淀粉酶的活力。结果：样本于4 ℃保存达到3 h时,胆汁α淀粉酶活力较30 min下降0.73个百分点。保存时间在12~72 h时,胆汁α淀粉酶活力较30 min下降2.11个百分点。保存时间延长至30 d,胆汁α淀粉酶活力较30 min下降3.94个百分点（P>0.05）,说明在4 ℃保存30 d内,胆汁α淀粉酶活力无明显变化。样本于离心3 000 r/min后,胆汁α淀粉酶较原液下降0.16%,8 000 r/min后胆汁α淀粉酶活力较原液上升4.74个百分点。离心8 000 r/min较离心3 000 r/min胆汁α淀粉酶活力上升4.91个百分点（P>0.05）,说明离心速度不超过8 000 r/min时,胆汁α淀粉酶活力无明显变化。结论：胆汁于4 ℃保存30 d内,离心速度不超过8 000 r/min时,胆汁α淀粉酶活力相对稳定。

Objective To study the effect of storage time and centrifugation speed on the activity of biliary α-amylase and the factors which affect the activity of α-amylase. Methods A total of 18 cases were randomly selected from 27 cases with endoscopic retrograde cholangiopancreatography in our hospital. The activity of biliary α-amylase was measured by iodine-starch colorimetry after bile samples were stored at 4℃ for 30 min, 3 h, 12 h, 24 h, 72 h and 30 d respectively, which was to study storage time in 6 groups each 18 cases. The bile samples in other 9 cases were used to study centrifugation speed including one group without sample centrifugation and the other two groups with sample centrifugation at 3 000 r/min or 8 000 r/min respectively. Results The activity of α- amylase decreased 0.73%, 2.11% and 3.94% in the bile stored at 4℃ for 3 h, 12~72 h or stored to 30 d respectively when compared with that stored 30 min (P>0.05), which indicated that the activity of biliary α-amylase did not change significantly for a period of storage 30 d at 4℃. The activity of biliary α- amylase decreased 0.16% after the centrifugation of 3 000 r/min compared with that without centrifugation, and increased 4.74% after the centrifugation of 8 000 r/min. The increase of 4.91% in the activity of biliary α-amylase was found at 8 000 r/min compared with that at 3 000 r/min(P>0.05), which indicated that the activity of biliary α-AMY had no obvious change when the centrifugal speed did not exceed 8 000 r/min. Conclusions The activity of biliary α-amylase would be relatively stable when bile is stored at 4℃ for 30 d and the centrifugal speed is 8 000 r/min or less.