论文部分内容阅读
以电刺激内脏大神经或耳尖部皮肤测定清醒家兔内脏或皮肤痛阈,观察中脑导水管周围灰质(PAG)中阿片肽和去甲肾上腺素在内脏镇痛和皮肤镇痛中的作用。结果:PAG内微量注射α受体阻断剂酚妥拉明(5μg/μl),皮肤痛阈明显升高,并增强和延长电针镇皮肤痛,但内脏痛阈无明显变化。微量注射β受体阻断剂普萘洛尔(5μg/μl),内脏痛阈和皮肤痛阈均无变化。PAG内微量注射阿片受体激动剂依托啡(1 μg/μl)后,内脏痛阈及皮肤痛阈明显上升,且可被纳洛酮(0.4mg/kg)iv所翻转。提示PAG内去甲肾上腺素α受体参与皮肤痛的调制,而阿片肽参与皮肤痛和内脏痛的调制。
The visceral or dermatological pain threshold of awake rabbits was measured by electrical stimulation of the visceral nerve or the auricle area. The effects of opioid peptide and norepinephrine in the midbrain periaqueductal gray (PAG) on visceral and skin pain were observed. Results: Microinjection of phentolamine (5μg / μl), a parenteral injection of parenterally into the PAG, markedly increased the pain threshold of the skin and enhanced and prolonged the electroacupuncture skin patches, but there was no significant change in the visceral pain threshold. Propranolol (5μg / μl), a microinjection ofβ-blocker, showed no change in visceral pain threshold and skin pain threshold. Microinjection of opioid receptor agonist etoposide (1 μg / μl) into PAG markedly increased visceral pain threshold and skin pain threshold, and was reversed by naloxone (0.4 mg / kg) iv. Suggesting that norepinephrine alpha receptors are involved in the modulation of cutaneous pain in PAG, whereas opioid peptide is involved in the modulation of cutaneous and visceral pain.