电刺激大白鼠、兔、猫、猴和人体的中脑中央灰质或向中央灰质注射微量吗啡、内源性吗啡样物质

可以抑制由各种伤害性刺激作用于周围神经、皮肤、内脏或牙髓所引起的疼痛

而且这种抗痛作用能为纳洛酮部分或完全逆转。此外

中央灰质也是鸦片受体和内源性吗啡样物质产生得比较多的一个部位。由此可见

中央灰质是脑内一个重要的痛觉调制结构。然而

An apparatus of exposed type for restraining the rat in our acupunc- ture analgesia research has been used. During the experiment the rat was restrained on a wooden base having a shallow trough with two canvas- bands which passed over the posterior of the animal's shoulders and the anterior of its coxae respectively. Tail-flick and screaming in response to electrical stimulation of the tail skin of rat were taken as indices of pain. The experiments were divided into three groups:1) the unilateral elec- trolytic lesions of the midbrain central gray

2) bilateral electrolytic les- ions of the central gray

3) sham operation. The effects of acupuncture analgesia in the animals with unilateral and the bilateral electrolytic les- ions of the central gray were markedly reduced

while no significant change of effect was noted in the third group. It is suggested that the midbrain central gray might play an important role in the process of acupuncture analgesia.