Nishimura S, Fukushima O, Ishikura H, Takahashi T, Matsunami M, Tsujiuchi T, Sekiguchi F, Naruse M, Kamanaka Y, Kawabata A
Division of Pharmacology and Pathophysiology, Kinki University School of Pharmacy, 3-4-1 Kowakae, Higashi-Osaka, 577-8502, Japan.
Gut. 2009 Jun;58(6):762-70. doi: 10.1136/gut.2008.151910. Epub 2009 Feb 6.
Hydrogen sulfide (H(2)S) is formed from l-cysteine by multiple enzymes including cystathionine-gamma-lyase (CSE) in mammals, and plays various roles in health and disease. Recently, a pronociceptive role for H(2)S in the processing of somatic pain was identified. Here, the involvement of H(2)S in pancreatic pain is examined.
Anaesthetised rats or mice received an injection of NaHS, a donor for H(2)S, or capsaicin into the pancreatic duct, and the expression of spinal Fos protein was detected by immunohistochemistry. Pancreatitis was created by 6 hourly doses of caerulein in unanaesthetised mice, and pancreatitis-related allodynia/hyperalgesia was evaluated using von Frey hairs. CSE activity and protein levels in pancreatic tissues were measured using the colorimetric method and western blotting, respectively.
Either NaHS or capsaicin induced the expression of Fos protein in the superficial layers of the T8 and T9 spinal dorsal horn of rats or mice. The induction of Fos by NaHS but not capsaicin was abolished by mibefradil, a T-type Ca(2+) channel blocker. In conscious mice, repeated doses of caerulein produced pancreatitis accompanied by abdominal allodynia/hyperalgesia. Pretreatment with an inhibitor of CSE prevented the allodynia/hyperalgesia, but not the pancreatitis. A single dose of mibefradil reversed the established pancreatitis-related allodynia/hyperalgesia. Either the activity or protein expression of pancreatic CSE increased after the development of caerulein-induced pancreatitis in mice.
The data suggest that pancreatic NaHS/H(2)S most probably targets T-type Ca(2+) channels, leading to nociception, and that endogenous H(2)S produced by CSE and possibly T-type Ca(2+) channels are involved in pancreatitis-related pain.
在哺乳动物中，硫化氢（H₂S）由包括胱硫醚-γ-裂解酶（CSE）在内的多种酶从L-半胱氨酸生成，并在健康和疾病中发挥多种作用。最近，已确定H₂S在躯体痛觉处理中具有促痛觉过敏作用。在此，研究H₂S在胰腺疼痛中的作用。
给麻醉的大鼠或小鼠经胰管注射H₂S供体硫氢化钠（NaHS）或辣椒素，通过免疫组织化学检测脊髓Fos蛋白的表达。在未麻醉的小鼠中，每6小时注射一次蛙皮素以诱发胰腺炎，并使用von Frey毛发评估胰腺炎相关的异常性疼痛/痛觉过敏。分别使用比色法和蛋白质印迹法测量胰腺组织中的CSE活性和蛋白质水平。
NaHS或辣椒素均可诱导大鼠或小鼠T8和T9脊髓背角浅层Fos蛋白的表达。T型钙通道阻滞剂米贝地尔可消除NaHS而非辣椒素诱导的Fos表达。在清醒小鼠中，重复注射蛙皮素可诱发胰腺炎并伴有腹部异常性疼痛/痛觉过敏。用CSE抑制剂预处理可预防异常性疼痛/痛觉过敏，但不能预防胰腺炎。单次注射米贝地尔可逆转已建立的胰腺炎相关异常性疼痛/痛觉过敏。在小鼠发生蛙皮素诱导的胰腺炎后，胰腺CSE的活性或蛋白质表达均增加。
数据表明胰腺NaHS/H₂S很可能作用于T型钙通道，导致伤害感受，并且CSE以及可能还有T型钙通道产生的内源性H₂S参与了胰腺炎相关疼痛。
