He Lihua, Li Xiangrui, Hua Tianmiao, Bao Pinglei, Ma Rui, Zhou Yifeng
Hefei National Laboratory for Physical Sciences at Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, P.R. China.
Brain Res. 2005 Oct 26;1060(1-2):81-8. doi: 10.1016/j.brainres.2005.08.036. Epub 2005 Oct 5.
Chronic opiate exposure leads to maladaptive changes in brain function. In view of the localization of opiate receptors in mammalian visual system, chronic opiate exposure is likely to affect the visual responses properties of V1 neurons. Using in vivo single-unit recording, we here showed that chronic morphine treatment resulted in the functional abnormality of primary visual cortical cells. When compared with saline-treated (as control) cats, cortical neurons in morphine-treated cats exhibited higher spontaneous activity, lower signal-to-noise ratios and weaker orientation and direction selectivity. However, re-exposure with morphine could significantly improve the function of V1 neurons in morphine-treated cats. These findings demonstrated that chronic morphine treatment could significantly degrade the response properties of V1 neurons and may lead to a function dependence on morphine in visual cortical cells.
长期接触阿片类药物会导致大脑功能出现适应性不良变化。鉴于阿片受体在哺乳动物视觉系统中的定位，长期接触阿片类药物可能会影响V1神经元的视觉反应特性。我们在此通过体内单单位记录表明，长期吗啡治疗导致初级视觉皮层细胞功能异常。与生理盐水处理（作为对照）的猫相比，吗啡处理的猫的皮层神经元表现出更高的自发活动、更低的信噪比以及更弱的方向和方向选择性。然而，再次接触吗啡可显著改善吗啡处理的猫中V1神经元的功能。这些发现表明，长期吗啡治疗可显著降低V1神经元的反应特性，并可能导致视觉皮层细胞对吗啡产生功能依赖性。
