产前使用硫酸特布他林促进早产大鼠肺液转运的研究

摘要

目的：观察β2受体激动剂硫酸特布他林对早产新生大鼠肺液转运的影响及机制。方法随机将孕鼠分为5组，对照组，早产组，特布他林低、高剂量组及地塞米松组，于受孕后第16天起以灌胃方法连续3 d分别给予不同药物。对照组取足月分娩新生鼠，其余各组大鼠于孕第19天行剖宫产，取早产鼠；新生鼠处死后取肺组织，测定肺组织湿重/干重之比、Na+，K+-ATP酶活性和环磷酸腺苷（cAMP）水平。结果五组新生鼠肺组织湿重/干重、Na+，K+-ATP酶活性以及cAMP水平的差异均有统计学意义（P均<0.01）。肺组织湿重/干重，以早产组最高，对照组最低；高剂量组低于低剂量组和地塞米松组，差异有统计学意义（P均<0.05）。Na+，K+-ATP酶活性，以早产组最低，高剂量组最高；地塞米松组、低剂量组和高剂量组均较早产组升高；高剂量组高于低剂量组和地塞米松组，差异均有统计学意义（P均<0.05）。cAMP水平，以早产组最低，高剂量组最高；地塞米松组、低剂量组和高剂量组均较早产组升高；高剂量组高于低剂量组和地塞米松组，差异均有统计学意义（P均<0.05）。结论产前使用β2受体激动剂硫酸特布他林，可降低早产新生大鼠肺组织湿重/干重之比，提高肺组织cAMP水平和增加Na+，K+-ATP酶活性。%Objectives To investigate the effect and mechanism of terbutaline sulfate on pulmonary fluid transport in pre-mature rats. Methods Pregnant rats were randomly divided into 5 groups (control group, premature group, low-dose terbutaline group, high-dose terbutaline group and dexamethasone group). Drugs were administered by gavage after rats were fertilized for 16 days and continued for 3 days. Premature rats were taken out from the 19 days pregnant rats, and mature rats were delivered on the due day. Lungs were collected, and the ratio of pulmonary wet weight to dry weight (W/D), Na+, K+-ATP ase activity and concentration of cyclic adenosine monophosphate (cAMP) were measured in lungs. Results The W/D rate, Na+,K+-ATPase acti-vity and cAMP concentration in lungs had significant difference among different groups (P<0.01). The W/D rate was highest in premature group and lowest in the control group. It was lower in the high-dose terbutaline group than in the low-dose terbutaline group and the dexamethasone group (P<0.05). The Na+,K+-ATPase activity was lowest in premature group and highest in high-dose terbutaline group. It was higher in dexamethasone group, low-dose terbutaline group, and high-dose terbutaline group than in premature group, and it was higher in high-dsoe terbutaline group than in low-dose terbutaline group and dexamethasone group (P<0.05). The cAMP levle was lowest in premature group and highest in high-dose terbutaline group. It was higher in dexamethasone group, low-dose terbutaline group, high-dose terbutaline group than in premature group, and it was higher in high-dose terbutaline group than in low-dose terbutaline group and dexamethasone group (P<0.05). Conclusions Terbutaline sulfate facilitates lung fluid transport in premature rats, leading to reduce the W/D rate in terbutaline-treated group. We speculate that this effect is related to the increased cAMP level and Na+, K+-ATPase activity in lung tissue.