Different purinergic receptors lead to intracellular calcium increases in pancreatic ducts

摘要: Extracellular adenosine 5’-triphosphate (ATP) has been described to act as a regulator in many cells and tissues, including epithelia, the gastrointestinal tract ATP is one of substances involved non-cholinergic non-adrenergic control. However, very little known about effect on pancreatic ducts, which normally secrete bicarbonate-rich fluid response secretin. Hence, aim our present study was test other nucleotides intracellular Ca2+ activity ([Ca2+]i) thereby get information purinergic receptors that might play role regulation bicarbonate transport. Native intralobular ducts were obtained from rat pancreas [Ca2+]i 10–20 measured using fura-2 method. (10–4 mol/l) evoked characteristic biphasic transient duct cells. Nucleotides, used classify P2 receptors, acted with following potency peak ducts: uridine (UTP) ≥ >inosine 2-methylthio-ATP > β,γ-methyl-ATP adenosine. although responses UTP similar, plateau nearly doubled UTP. Moreover, one-third studied, had no cell Ca2+, while normal. In further experiments we found removal extracellular Mg2+ increased ATP. 2’&3’-O-(4-benzoylbenzoyl) (BzATP) monophasic slower increase [Ca2+]i, inhibited by or addition 4, 4’-diisothiocyanatostilbene-2, 2’-disulphonic acid (DIDS). Taken together, data indicate there are two types through can act. These pharmacologically P2U P2Z may correspond P2Y2 P2X7 receptors.