Second Department of Pharmacology, School of Pharmaceutical Sciences, Kyushu University of Health and Welfare, 1714-1 Yoshino-machi, Nobeoka-shi, Miyazaki 882-8508 Japan.
Eur J Pharmacol. 2012 May 5;682(1-3):56-61. doi: 10.1016/j.ejphar.2012.02.005. Epub 2012 Feb 17.
Carnosine is a biologically active dipeptide that is found in fish and chicken muscle. Recent studies have revealed that carnosine has neuroprotective activity in zinc-induced neural cell apoptosis and ischemic stroke. In the present study, we examined the expression of carnosine in the spinal cord, and the antinociceptive potency of carnosine in a mouse model of inflammation-induced nociceptive pain. Immunohistochemical studies with antiserum against carnosine showed an abundance of carnosine-immunoreactivity in the dorsal horn of the mouse spinal cord. Double-immunostaining techniques revealed that carnosine was expressed in the neurons and astrocytes in the spinal cord. Oral administration of carnosine attenuated the number of writhing behaviors induced by the intraperitoneal administration of 0.6% acetic acid. Treatment with carnosine also attenuated the second phase, but not the first phase, of the nociceptive response to formalin. Moreover, intrathecal, but not intraplanter, administration of carnosine attenuated the second phase of the nociceptive response to formalin. Our immunohistochemical and behavioral data suggest that carnosine has antinociceptive effects toward inflammatory pain, which may be mediated by the attenuation of nociceptive sensitization in the spinal cord.
肌肽是一种存在于鱼肉和鸡肉中的生物活性二肽。最近的研究表明，肌肽具有锌诱导的神经细胞凋亡和缺血性中风的神经保护活性。在本研究中，我们检测了肌肽在脊髓中的表达以及肌肽在炎症诱导的痛觉过敏疼痛的小鼠模型中的镇痛效力。用肌肽抗血清进行的免疫组织化学研究显示，肌肽在小鼠脊髓背角中大量存在。双免疫染色技术显示，肌肽在脊髓中的神经元和星形胶质细胞中表达。肌肽的口服给药可减轻 0.6%乙酸腹腔内给药引起的扭体行为的数量。肌肽治疗还可减轻对福尔马林的痛觉反应的第二阶段，但不减轻第一阶段。此外，鞘内但不是足底内给予肌肽可减轻对福尔马林的痛觉反应的第二阶段。我们的免疫组织化学和行为学数据表明，肌肽对炎症性疼痛具有镇痛作用，这可能是通过减轻脊髓中的伤害感受敏化来介导的。
