Luzzi S, Franchi-Micheli S, Ciuffi M, Pajani A, Zilletti L
J Auton Pharmacol. 1986 Sep;6(3):163-9. doi: 10.1111/j.1474-8673.1986.tb00641.x.
The effects of phosphonic analogues of GABA, beta-alanine and glycine on guinea-pig ileum longitudinal muscle were measured. Aminomethylphosphonic acid (AMPh) and 2-aminoethylphosphonic acid (2-AEPh) were devoid of any effect both in non-stimulated preparations and in electrically-stimulated preparations. The phosphonic analogue of GABA, 3-aminopropylphosphonic acid (3-APPh) possessed a GABAB agonistic effect (relaxation and inhibition of twitch response) at doses of 10(-3)M. No agonistic effect on GABAA receptors was observed. 3-APPh at doses tested (2 X 10(-4)M and 10(-3)M) also displayed antagonistic action on the effects of GABAB agonists producing a parallel shift of the log dose-effect curves of GABA- and (-)-baclofen-inhibition of twitch responses. In contrast 3-APPh did not antagonize the inhibitory effect of morphine and noradrenaline. The contractile effect of GABA, mediated via GABAA receptors, was unaffected by 3-APPh(10(-3)M). It is concluded that 3-APPh is a partial agonist at the GABAB site in guinea-pig ileum.
测定了γ-氨基丁酸（GABA）、β-丙氨酸和甘氨酸的膦酸类似物对豚鼠回肠纵肌的作用。氨甲基膦酸（AMPh）和2-氨基乙基膦酸（2-AEPh）在非刺激制剂和电刺激制剂中均无任何作用。GABA的膦酸类似物3-氨基丙基膦酸（3-APPh）在10⁻³M剂量时具有GABAB激动效应（松弛和抑制抽搐反应）。未观察到对GABAA受体的激动效应。在所测试的剂量（2×10⁻⁴M和10⁻³M）下，3-APPh对GABAB激动剂的作用也表现出拮抗作用，使GABA和（-）-巴氯芬抑制抽搐反应的对数剂量-效应曲线平行移动。相比之下，3-APPh不拮抗吗啡和去甲肾上腺素的抑制作用。通过GABAA受体介导的GABA收缩效应不受3-APPh（10⁻³M）影响。结论是3-APPh是豚鼠回肠中GABAB位点的部分激动剂。
