促皮质素对甲醛引起大鼠脊髓内生长抑素的影响

目的：研究促皮质素（Ｃｏｒ）对甲醛引起大鼠脊髓内生长抑素及其合成的影响，方法：采用免疫组织化学，免疫组织化学双重染色法和原位杂交技术。结果：足底注射甲醛使大鼠脊髓背角内ＦＬＩ，ＳｏｍＬＩ，Ｓｏｍ－ＬＩ／ＦＬＩ和ＰＰＳ－ｍＲＮＡ神经元数均对较对照组显著增多，单独ｉｐＣｏｒ对脊髓背角ＦＬＩ和Ｓｏｍ－ＬＩ无明显影响。但是，ｉｐＣｏｒ显著抑制甲醛引起的背角内ＦＬＩ，Ｓｏｍ－ＬＩ，Ｓｏｍ－ＬＩ／ＦＬＩ和ＰＰ

Effect of corticotrophin on formaldehyde-induced somatostatin of spinal cord in rats]

AIM: To study the effect of corticotrophin (Cor) on somatostatin (Som) and its synthesis in spinal dorsal horn induced by formaldehyde in rats. METHODS: Using double immunohistochemical stainings, and in situ hybridization. RESULTS: Two hours after s.c. formaldehyde (5%, 200 microL) in one hindpaw of rats, the neurons of c-fos-like immunoreactivity (FLI), somatostatin-like immunoreactivity (Som-LI), Som-LI/FLI, and perprosomatostatin mRNA (PPS-mRNA) in ipsilateral spinal dorsal horn were increased obviously, as compared with the control group. The FLI and Som-LI of spinal cord were not changed by i.p. Cor. Cor (25 or 12.5 U.kg-1, i.p.) inhibited the formaldehyde-evoked FLI, Som-LI, Som-LI/FLI, and PPS-mRNA of spinal cord in a dose-dependent manner. The decrease of c-fos or Som level due to i.p. Cor in rats of chronic pain was prevented by raphe nuclei injected cyproheptadine, but not by bicuculline, naloxone, or phentolamin injected to raphe nuclei. CONCLUSION: The formaldehyde-evoked c-fos expression, Som, and Som synthesis of spinal cord were suppressed by Cor through the serotonin receptor of raphe nuclei.