大鼠中脑导水管周围灰质及侧脑室注入促肾上腺皮质激素对脊髓背角神经元放电的影响

THE EFFECTS OF INJECTION OF ADRENOCORTICOTROPIN INTO PERIAQUEDUCTAL GRAY AND LATERAL CEREBROVENTRICLE ON THE NEURONAL DISCHARGES OF SPINAL DORSAL HORN NEURONS IN RATS

目的：观察中脑导水管周围灰质及侧脑室注入促肾上腺皮质激素（ＡＣＴＨ）对脊髓背角神经元放电的影响。方法：用玻璃微电极细胞外记录脊髓背角神经元放电。ＰＡＧ或侧脑室注射不同剂量ＡＣＴＨ，给药后于不同时间记录神经元的电活动。结果：在３０个神经元中，有２２个被ＰＡＧ注入ＡＣＴＨ抑制；１５个神经元中，有１４个被侧脑室注入ＡＣＴＨ兴奋。结果表明：ＡＣＴＨ在ＰＡＧ水平有抗伤害作用。

The effects of periaqueductal gray (PAG) and intracerebroventricular (i.c.v.) injection of adrenocorticotropin (ACTH) on the nociceptive discharges of spinal dorsal horn neurons(DHN) were investigated. Extracellular recordings in DHN were made using glass micropipette filled with 2% pontamine sky blue in 0.5mmol sodium acetate. Nociceptive discharges were recorded during injection of ACTH (0.625, 1.25, 2.5 μg/ 5μl). Results: Twenty two out of 30 DHN were inhibited by injection of ACTH in PAG, while 14 out of 15 DHN were excited by i.c.v. injection of ACTH. These results suggest ACTH in the PAG may play an antinociceptive role, while ACTH in cerebroventricle may facilitate nociception.