Kettunen Petronella, Kyriakatos Alexandros, Hallén Kristofer, El Manira Abdeljabbar
Nobel Institute for Neurophysiology, Department of Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden.
Neuron. 2005 Jan 6;45(1):95-104. doi: 10.1016/j.neuron.2004.12.022.
Endocannabinoids act as retrograde signals to modulate synaptic transmission. Little is known, however, about their significance in integrated network activity underlying motor behavior. We have examined the physiological effects of endocannabinoids in a neuronal network underlying locomotor behavior using the isolated lamprey spinal cord. Our results show that endocannabinoids are released during locomotor activity and participate in setting the baseline burst rate. They are released in response to mGluR1 activation and act as retrograde messengers. This conditional release of endocannabinoids can transform motoneurons and crossing interneurons into modulatory neurons by enabling them to regulate their inhibitory synaptic inputs and thus contribute to the modulation of the locomotor burst frequency. These results provide evidence that endocannabinoid retrograde signaling occurs within the locomotor network and contributes to motor pattern generation and regulation in the spinal cord.
内源性大麻素作为逆行信号来调节突触传递。然而，关于它们在运动行为所依赖的整合性网络活动中的意义，人们所知甚少。我们使用分离的七鳃鳗脊髓，研究了内源性大麻素在运动行为所依赖的神经元网络中的生理作用。我们的结果表明，内源性大麻素在运动活动期间释放，并参与设定基线爆发频率。它们响应代谢型谷氨酸受体1（mGluR1）的激活而释放，并作为逆行信使发挥作用。内源性大麻素的这种条件性释放可使运动神经元和交叉中间神经元通过调节其抑制性突触输入而转变为调节性神经元，从而有助于调节运动爆发频率。这些结果提供了证据，表明内源性大麻素逆行信号在运动网络中发生，并有助于脊髓中运动模式的产生和调节。
