摘要
目的:观察一氧化氮(nitric oxide,NO)供体左旋精氨酸(L-argnine,L-Arg)对小鼠回肠自主收缩幅度的影响,探讨β-肾上腺素能受体在NO抑制小鼠回肠自主收缩中的作用。方法:应用张力换能器记录标本自主收缩的方法,以回肠肌条自主收缩幅度变化为指标,观察一氧化氮合酶(nitric oxide synthase,NOS)抑制剂L-NNA,可溶性鸟苷酸环化酶(soluble guanylyl cyclase,sGC)抑制剂ODQ(1H-[1,2,4]oxadiazolo[4,3-α]quinoxalin-1-one),β-肾上腺素能受体激动剂异丙肾上腺素(Isoprenaline,ISO)和拮抗剂普萘洛尔(Propranolol)对NO作用的影响。结果:①L-Arg抑制小鼠回肠自主收缩幅度,呈浓度依赖性。②L-NNA(3×10-4mol/L),ODQ(3×10-4mol/L)均减弱L-Arg的抑制效应。③Propranolol(3×10-6mol/L)明显减弱L-Arg的抑制效应。④ISO(1×10-7mol/L)明显增强L-Arg的抑制效应。而Propranolol(3×10-6mol/L)和ISO(1×10-7mol/L)孵育组,L-Arg的抑制作用无明显变化。结论:L-Arg经NOS催化生成NO后经cGMP途径发挥对小鼠回肠自主收缩的抑制作用,β-受体途径也部分参与了NO的作用过程。
Aim： To investigate the influence of L-arginine（ NO donors, L-Arg） on spontaneous contractions of ileum in mice and study the effects of activation of β-adrenoceptor on NO-induced inhibtion in spontaneous contractions of ileum. Methods： The method of spontaneous contractions recording was used to investigate the effect of L-NNA, ODQ, Isoprenaline（ β-adrenoceptor agonist） and Propranolol（β-adrenoceptor antagonist） on NO-induced inhibition in spontaneous contractions of ileum. Results： ①L-Arg inhibited the spontaneous contractions of ileum and had concentration-response relationship. ②L-NNA（3 × 10 ^-4mol/L）, ODQ （3 × 10^- 6mol/L） relieved the inhibitory effect of L-Arg in ileum . ③Propronalol （3 × 10^- 6mol/L） decreased significantly the inhibitory effect of L-Arg. ④Iso（1 × 10^-7/mol/L） increased the inhibitory effect of L-Arg. After Iso（ 1 × 10^- 7mol/L） and Propronalol（3 × 10^- 6mol/L） being coapplied, the inhibitory effect of L-Arg was not changed. Conclusion： NOS catalyzed L-Arg and produced NO. NO exerted its inhibitory effect by the cGMP pathway, the activation of β-adrnoceptor was partly involved in NO-induced relaxation in ileum.
出处
《中国应用生理学杂志》
CAS
CSCD
北大核心
2007年第1期111-115,共5页
Chinese Journal of Applied Physiology
