摘要
目的观察鞘内注射腺苷A_1受体激动刺笨基异丙基腺苷(R-P1A)对吗啡和可乐定镇痛作用的影响。方法健康雄性SD大鼠,鼠龄8～10周,体重250～300 g．鞘内置管成功的85只大鼠随机分为17组,每组5只,对照组、R-PIA0．4组、R-PIA0．8组、R-PIA1．0组、茶碱组、吗啡2．0组、吗啡5．0组、可乐定2．0组、可乐定15．0组、R-PIA+吗啡2．0组、R-PIA+吗啡5．0组、R-PIA+可乐定2．0组、R- PIA+可乐定15．0组、可乐定+吗啡组均鞘内注射生理盐水,15min后分别注射生理盐水、R-PIA 0．4μg、R-PIA 0．8μg、R·PIA 1．0μg、茶碱50μg、吗啡2．0μg、吗啡5．0μg、可乐定2．0μg、可乐定15．0μg、R- P1A 0．4μg+吗啡2．0μg、R-PIA 0．4μg+吗啡5．0μg、R-PIA 0．4μg+可乐定2．0μg、R-PIA 0．4μg+可乐定15．0μg、可乐定2．0μg+吗啡2．0μg；R-PIA+吗啡+茶碱组、R-PIA+可乐定+茶碱组、可乐定+吗啡+茶碱组鞘内注射茶碱50μg,15 min后分别注射R-PIA 0．4μg+吗啡5．0μg、R-PIA 0．4μg+可乐定15．0μg、可乐定2．0μg+吗啡2．0μg,每次给药容积均为10μl、注药后5、10、20、30、40、60 min时测定大鼠热辐射甩尾反应潜伏期(TFL),用最大效应百分比(MPE)[(注药后TFL-TFL的基础值)/(10．0- TFL的基础值)×100%]评价镇痛效果。结果高剂量R-PIA、吗啡、可乐定可升高MPE,R-PIA可增强吗啡、可乐定的镇痛作用,可被茶碱完全阻断,吗啡可增强可乐定的镇痛作用,可被茶碱部分阻断；可乐定可增强吗啡的镇痛作用。结论大鼠鞘内注射R-PIA可增强吗啡和可乐定的镇痛作用,其机制可能与活化脊髓内腺苷受体有关。
Objective To investigate the analgesic effect of adenosine A1 receptor agonist R（ - ）-N6-（2- phenyl-isopropyl）-adenosine （R-HA） injected into the brainstem medial pontine reticular formation （mPRF） and the underlying mechanism. Methods Sixty male SD rats aged 8-10 weeks weighing 250-300 g were used in this study. The animals were anesthetized with intraperitoneal 10% chloral hydrate 300 mg. kg^-1. A 24-gauge stainless steel cannula was inserted into mPRF on one side using a stereotaxic apparatus. One week after cannulation the animals were randomly divided into 12 groups （ n = 5 each） ： group Ⅰ control received normal saline （NS） 0.3 μl; group Ⅱ ,Ⅲ, Ⅳ received R-HA 0.5, 1.0 and 2.0 μg in NS 0.3 μl respectively; group Ⅴ theophylline （an adenosine receptor antagonist） 5.0 μg ; group Ⅵ 8-cyclopentyl- 1,3-dipropylxanthine （ DPCPX, an adenosine A l receptor antagonist） 1.0 μg; group Ⅶ gliben-clamide （an ATP-sensitive k＋ channel blocker） 5.0μg; group Ⅷ 4-aminopyridine （4-AP, a voltage dependent K^＋ -channel blocker） 5.0 μg; group Ⅸ theophylline 5.0 μg ＋ R-PIA 2.0 μg; group Ⅹ DPCPX 1.0 μg ＋ R-HA 2.0 μg; group Ⅺ glibenclamide 5.0 μg ＋ R-HA 2.0 μg and group Ⅻ 4- AP 5.0 μg ＋ R- PIA 2.0 μg. All the drugs injected into mPRF were in 0.3 μl of NS. In group Ⅸ -Ⅻ R- HA 2.0 μg was administered 15 min after pretreatment with theophylline, DPCPX, glibenclamide or 4-AP. Analgesia was determined using the tail-flick latency （TFL） （the time between the onset of the radiant heat stimulus and voluntary tail withdrawal） at 5, 15, 30, 45, 60 and 90 min after R-HA injection into mPRF. Maximal possible effect （MPE） was calculated. MPE （TFL after drug - baseline TFL） / （ 10.0 - baseline TFL） ~ 100 %. Results R-PIA 0.5-2.0μg injected into mPRF produced significant analgesia in a dose-dependent manner. Pretreatment with theophylline or DPCPX completely reversed the analgesic effect of R-PIA while pretreatment with glibenclam
出处
《中华麻醉学杂志》
CAS
CSCD
北大核心
2006年第8期688-691,共4页
Chinese Journal of Anesthesiology
关键词
腺苷
吗啡
可乐定
蛛网膜下腔
镇痛
Adenosine
Morphine
Clonidine
Subarachnoid space
Analgesia
