Garcia-Rill E, Skinner R D, Jackson M B, Smith M M
Brain Res Bull. 1983 Jan;10(1):57-62. doi: 10.1016/0361-9230(83)90075-8.
These studies were designed to determine whether or not substantia nigra (SN) neurons project to the mesencephalic locomotor region (MLR). An attempt was made to activate SN neurons antidromically from the same site which induced locomotion on a treadmill following a precollicular-postmammillary transection in the same animal. Less than 10% of posterior SN neurons were activated antidromically from the physiologically-identified MLR. These results support previous anatomical findings describing a sparse projection from the SN to the MLR [5]. Locomotion on a treadmill was elicited at low current strengths (20-50 muA) from an area around the cuneiform nucleus in the posterior mesencephalon. This area included the lateral central gray, mesencephalic trigeminal root, dorsal brachium conjunctivum and nucleus tegmenti pedunculopontinus (NTPP) and perhaps anterodorsal locus coeruleus. Stimulation of the area just described induced a complete stepping cycle with a flexion phase and a three-part extension phase. Stimulation of the posterior SN produced spastic locomotion on a treadmill at higher current strengths (70 muA) in cats with a precollicular-postmammillary transection.
这些研究旨在确定黑质（SN）神经元是否投射到中脑运动区（MLR）。研究人员尝试在同一动物进行视丘前 - 乳头体后横断后，从跑步机上诱导运动的同一部位逆向激活SN神经元。在生理上确定的MLR中，不到10%的黑质后部神经元被逆向激活。这些结果支持了先前关于从黑质到中脑运动区稀疏投射的解剖学发现[5]。在中脑后部楔形核周围区域，以低电流强度（20 - 50微安）可引发跑步机上的运动。该区域包括外侧中央灰质、中脑三叉神经根、背侧结合臂和脚桥被盖核（NTPP），可能还包括蓝斑前背侧核。在视丘前 - 乳头体后横断的猫中，刺激上述区域可在跑步机上以更高电流强度（70微安）产生完整的踏步周期，包括屈曲阶段和三分伸展阶段。刺激黑质后部会在跑步机上产生痉挛性运动。
