Effects of intrathecally administered morphine and ketamine on nitric oxide synthase activity and nitric oxide production in the spinal cord
- VernacularTitle:鞘内联合应用吗啡和氯胺酮对神经痛大鼠脊髓NOS活性和NO产量的影响
- Author:
Hua CHEN
;
Jin ZHANG
;
Jianjun GUI
- Publication Type:Journal Article
- Keywords:
Nervous system diseases;
Morphine;
Ketamine;
Subarachnoid space;
Nitric-oxide synthase;
Nitric oxide
- From:
Chinese Journal of Anesthesiology
1994;0(03):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the effects of intrathecally administered morphine and ketamine on nitric oxide synthase (NOS) activity and nitric oxide content in the spinal cord.Methods Thirty-two male Wistar rats weighing 220-260 g were anesthetized with intraperitoneal chloral hydrate 300 mg?kg-1 . A catheter was implanted in subarachnoid space at lumbal region. Sciatic constriction injury (SCI) was produced by loose ligation of right sciatic nerve trunk with 4-0 cutgut. On the 4th postoperative day the animals were randomly divided into four groups of 8 animals :(1) control group (C); (2) morphine group (M);(3) ketamine group (K) and morphine-ketamine group (KM) . Morphine 20 ?g / ketamine 20 ?g / morphine 10 ?g + ketamine 10 ?g were injected intrathecally every day for 7 consecutive days in group M, K and KM. In control group normal saline was injected intrathecally instead of morphine and / or ketamine. The withdrawal latenvies to radiant heat focused on plantar surface were measured as radiant heat threshold before intrathecal administration of the analgesic (baseline) and 30 min after intrathecal administration of ketamine and / or morphine every day for 7consecutive days. The percentage of maximal possible effect ( MPE % ) was calculated : MPE % = (latency after intrathecal administration-baseline latency) / (radiant heat cut-off time-baseline latency) X 100% . After 7 days of intrathecal administration the animals were decapitated and the spinal cord was immediately removed and the lumbal spinal cord was dissected on ice. NOS activity and nitric oxide ( NO) content were measured by spectrophotometry. Results MPE % was significantly higher in group M and KM than in group C and K ( P
