摘要
目的探讨丁公藤碱降眼压作用的分子药理学机制。方法在恒定光源下用瞳孔尺测量兔瞳孔直径，用气动眼压计测量兔眼压，测量离体兔虹膜的收缩力，采用放射免疫法测定房水的环核苷酸含量。结果测定丁公藤碱缩瞳作用的ｐＤ２值为３．６０±０．１５，降眼压作用的ｐＤ２值为３．４９±０．０７，离体虹膜收缩作用的ｐＤ２值为６．３８±０．１２。Ｍ１～Ｍ３受体拮抗剂均可拮抗丁公藤碱的缩瞳作用、降眼压作用及离体虹膜收缩作用，其中以Ｍ３受体拮抗剂的拮抗作用最强。０．０１％丁公藤碱可使房水环磷酸腺苷（ｃｙｃｌｉｃａｄｅｎｏｓｉｎｅｍｏｎｏｐｈｏｓｐｈａｔｅ，ｃＡＭＰ）含量降低，环磷酸鸟苷（ｃｙｃｌｉｃｇｕａｎｏｓｉｎｅ３，５ｍｏｎｏｐｈｏｓｐｈａｔｅ；ｃＧＭＰ）含量升高。结论丁公藤碱的缩瞳和降眼压作用主要通过Ｍ３受体介导，其信号转导机制与环核苷酸系统相偶联。
Objective To investigate the
molecular pharmacological mechanism of lowering intraocular pressure of Erycibele alkaloid.
Methods Rabbit pupil diameter was measured by a pupillary ruler in constant illumination and
the intraocular pressure (IOP) was measured by pneumatonometer. Iris contracting force was
measured in an experiment of isolated rabbit iris. Radioimmune method was used to determine
the content of cyclonucleotide. Results The pD2 value (the affinity to Mreceptors of agonist) of
Erycibele alkaloid's miosis is 3.600.15 and its IOP lowering action is 3.490.07. In the isolated
iris contracting experiment, its pD2 value is 6.380.12. M3 receptor antagonist is the strongest
antagonist in inhibiting the miosis, IOP lowering action and isolated iris pupillary contracting
action of Erycibele alkaloid. 0.01% Erycibele alkaloid can cause the decrease of cAMP and the
increase of cGMP in the aqueous humor. Conclusions The effects of miosis and IOP lowering of
Erycibele alkaloid are all mediated by M3 receptor subtype and its signal transductive
mechanism is connected with cyclic nucleotide system.
出处
《中华眼科杂志》
CAS
CSCD
北大核心
1999年第3期171-173,共3页
Chinese Journal of Ophthalmology
基金
国家自然科学基金
广东省自然科学基金
关键词
丁公藤碱
缩瞳
降眼压
M受体亚型
分子药理学
Erycibele alkaloidMiosisIOP
loweringMuscarinic receptor subtypeCyclic nucleotide
