Maier R, Brugger M, Brückner H, Kamber B, Riniker B, Rittel W
Acta Endocrinol (Copenh). 1977 May;85(1):102-8.
The influence of positions 11 and 24 on hypocalcaemic potency and duration of action was examined. These positions are respectively occupied by threonine and glutamine in HCT, but by the basic amino acids lysine and arginine in SCT. Replacement of threonine by lysine trebled the hypocalcaemic potency of HCT and slightly prolonged its duration of action. Substitution of arginine for glutamine reduced the activity to about one tenth. The simultaneous introduction of both basic amino acids yielded an analogue intermediate in activity between those obtained by the single substitutions. The analogue [Bmp1, Va18, Lys11, Arg24]-HCT displayed the same effects as [Lys11]-HCT.
研究了第11位和第24位氨基酸对降钙素低血钙效力和作用持续时间的影响。在人降钙素（HCT）中，这两个位置分别由苏氨酸和谷氨酰胺占据，但在鲑鱼降钙素（SCT）中则由碱性氨基酸赖氨酸和精氨酸占据。用赖氨酸取代苏氨酸使HCT的降钙效力增加了两倍，并略微延长了其作用持续时间。用精氨酸取代谷氨酰胺使活性降低至约十分之一。同时引入这两种碱性氨基酸产生的类似物，其活性介于单次取代得到的类似物之间。类似物[Bmp1，Va18，Lys11，Arg24]-HCT与[Lys11]-HCT表现出相同的效果。
