可乐定对大鼠噪音避水应激所致胃溃疡的抑制作用

Inhibiting effect of Clonidine on the development of gastric ulcer due to stress elicited by noise plus water avoidance in rats

目的研究可乐定对大鼠噪音结合避水应激诱导的胃溃疡的抑制作用及对血浆皮质酮水平的影响.方法 48只成年雄性 SD 大鼠随机分为实验 A,B,C 组和对照组.A 组大鼠腹腔内注射0.5mL 可乐定(0.5mg·kg^(-1)),B 组腹腔内注射0.5mL 等渗盐水,C 组和对照组不注射.1h 后,A,B,C 三组均行噪音避水刺激.刺激4h 后,检测所有大鼠胃粘膜损伤指数和血浆皮质酮浓度.结果对照组大鼠胃粘膜光整完好,肉眼未见糜烂及溃疡.A,B,C 组大鼠胃粘膜均有不同程度的充血、水肿、糜烂及溃疡形成.A,B,C 组的应激溃疡指数分别为3.40±0.92,10.28±4.60,11.93±3.26,显著高于对照组(0,P<0.05).A 组溃疡指数明显低于 B,C 组(P<0.05);B,C 组间无显著差异(P>0.05).A,B,C 组中的血浆皮质酮的水平分别为20.35±4.12μg·L^1,31.60±4.08μg·L^(-1),30.74±4.77μg·L^(-1),明显高于对照组的水平(17.58±2.49 μg·L^(-1),P<0.05),A 组血浆皮质酮水平明显低于实验 B,C 组的水平(P<0.05),B、C 组间的血浆皮质酮水平无统计学差异(P>0.05).结论可乐定可减弱噪音避水应激诱导的胃粘膜损伤,并可抑制应激导致的血浆皮质酮水平的升高,对应激引起的大鼠胃粘膜损伤有明显的保护作用.

AIM To investigate the effects of clonidine pretreatment on stress ulcer(SU)and stress-induced plasma corticosterone(CORT)level in rats. METHODS The rat stress model was produced by exposure to noise plus water avoidance.Fourty-eight adult male SD rats were randomly divided into four groups (A,B,C and control).A,B and C groups separately received intraperitoneal administration(ip)of clonidine (0.5 mg·kg^(-1)),saline and no injection and underwent the given treatment of stress after 1h.Stress and administration(ip)of clonidine were waived in the control group.After 4h treatment of stress,all rats were killed to collect the gastric mucosal tissue and peripheral blood for evaluation of gastric lesion index(UI),pathological changes and measurement of plasma CORT concentration. RESULTS The gastric mucosal tissue of control group kept intact and no corrosive focus or ulcer was observed. The gastric mucosal tissue of A,B and C groups were found to have variant congestion,edema and development of corrosion or ulcer.The mean UI in A,B and C groups were 3.40±0.92,10.28±4.60,11.93±3.26 respectively, and significantly higher than in control group(0, P<0.05),whereas the UI of A group was lower than those of B and C groups(P<0.05).Compared with the control group(17.58±2.49μg·L^(-1)),the plasma CORT concentration of A,B and C groups were markedly higher (P<0.05),while the plasma CORT levels of A group(20.35 ±4.12μg·L^(-1))were lower than B group(31.60±4.08μg· L^(-1),P<0.05)and C group(30.74±4.77μg·L^(-1), P<0.05). CONCLUSION Clonidine could significantly inhibit strese- induced gastric mucosel lesion and response,which may be useful in preventing stress-elicited gastric mucosel damage.