急性胰腺炎（AP）是一种严重的炎症性疾病，其发病机制不明，且尚无有效的治疗手段。胰腺腺泡细胞(PAC)钙过载是触发AP发病的一个重要因素。防止PAC钙过载可为靶向治疗AP提供新思路。研究表明黄连素可改善小鼠AP的病理改变，但其机制不清楚。申请人在美国博士联合培养期间研究发现黄连素可明显抑制乙酰胆碱（ACh）诱发的PAC内钙振荡，进一步实验表明黄连素可与PAC的毒菌碱M3受体亚型（M3R）结合。因此我们推测“黄连素可通过抑制M3R减弱PAC内钙信号，从而减轻PAC内钙过载，防止胞内蛋白酶激活和PAC坏死”。本研究将在前期工作的基础上，利用膜片钳和钙成像技术进一步探讨黄连素调节PAC内钙信号的机制。主要内容：①黄连素抑制PAC内钙信号的药理机制；②黄连素作用的特异性靶点；③黄连素对AP模型小鼠的保护作用。本研究为阐明黄连素治疗AP的细胞机制和靶点提供重要的理论依据和实验基础。

Acute pancreatitis (AP) is a life-threatening serious inflammatory disease. Since the reasons for its pathogenesis are still unclear, the effective treatment of AP is still lack. Recent studies have shown that calcium overload in pancreatic acinar cells(PAC) is an important factor that triggers the onset of AP, which provides a novel therapeutic strategy for treatment of AP through the prevention of cell calcium overload.Emerging evidence shows that berberine can improve the pathological changes in AP model mice, but the cellular mechanism of improvement calcium overload in pancreatic acinar cells are still unclear. During a Chinese-American Ph.D. Co-training Program, the applicant investigated the berberine can significantly inhibit acetylcholine-induced PAC calcium oscillations. Further experiments confirmed that berberine can bind to the mycotoxin M3 receptor subtype (M3R) of PAC. Therefore, we hypothesized that berberine inhibits calcium signal in PAC through the M3 receptor, thereby reducing intracellular calcium overload and preventing intracellular protease activation and PAC necrosis.Based on our preliminary studies, this proposal will use patch clamp and Ca2+ imaging techniques to further study the effects of berberine on PAC intracellular Ca2+ signals. The main research aims include: (1) the pharmacological mechanism of berberine-induced inhibition in Ca2+ signal of PAC, (2) the specific target of berberine effect, and (3) the protective effect of berberine on the pathological injury during acute pancreatitis. This proposal will provide theoretical and experimental evidence to elucidate the cellular mechanisms and targets of berberine in the treatment of AP.