目的　研究烧伤早期心肌 Ｇｓ αｍ Ｒ Ｎ Ａ 表达水平的变化，探讨其在烧伤后心肌舒缩功能下降中的作用。方法　采用３０ ％ 体表面积Ⅲ度烫伤大鼠模型，测定伤前及伤后左心室收缩压（ Ｌ Ｖ Ｓ Ｐ） 、左心室压力最大上升与下降速率（ Ｌ Ｖ±ｄｐ／ｄｔｍａｘ） ，用ｄｏｔ ｂｌｏｔｔｉｎｇ 杂交技术测定心肌 Ｇｓ αｍ Ｒ Ｎ Ａ 表达水平的变化。结果　与对照组相比，烫伤组 Ｌ Ｖ Ｓ Ｐ、±ｄｐ／ｄｔｍａｘ 明显降低（ Ｐ＜ ００１） ，伤后３ 、６ 、９ 小时心肌 Ｇｓ αｍ Ｒ Ｎ Ａ 表达水平明显减少（ Ｐ＜００１） ，且与 Ｌ Ｖ Ｓ Ｐ、±ｄｐ／ｄｔ ｍａｘ 变化呈显著正相关（ ｒ 值分别为０８５ 、０８２ 、０８１ ， Ｐ＜ ００１） 。结论　烫伤后早期心肌 Ｇｓ αｍ Ｒ Ｎ Ａ 表达减少，是烧伤后心肌收缩功能降低的重要因素之一。 Objective To study the changes of Gs αm R N A expression in the early stage of burn injury and to explore the role of Gs αm R N A in the reduction of myocardial relaxation and relaxation after burn. Methods 30% body surface area Ⅲ degree scald rat model was used to measure the left ventricular systolic pressure (L V S P) and left ventricular pressure (L V ± dp / dt max) before and after injury. Dot blotting Changes of myocardial expression of Gs αm R N A by hybridization assay. Results Compared with the control group, the L V S P, ± dp / dtmax of the scald group was significantly decreased (P <001), and the expression of Gs αm R N A was significantly decreased at 3, 6,  01), and was positively correlated with the change of L V S P and ± dp / dt max (r = 085, 082, 081, P <001, respectively). Conclusions The decrease of Gs αm R N A expression in early postburn myocardium is one of the important factors in reducing myocardial contractile function after burn injury.