本實驗主要研究雨傘節(Bungarus multicinctus)蛇毒對大白鼠
血流力學因子的效應，及對單一心房肌細胞的影響。欲測定之血流
力學因子包括：平均血流量(mean blood flow, MBF)、一次心搏量(
stroke volume, SV)、脈波流量(pulstile blood flow, PBF)、股
動脈收縮壓(systolic blood pressure, SBP)、股動脈舒張壓(
diastolic blood pressure, DBP)、和心跳速率(heart rate, HR)，
並計算心輸出量(Cardiac output, CO)。另以離體大白鼠右心房肌，
利用細胞內記錄法(intracellular recording method)記錄單一心
肌細胞活動電位的振幅(amplitude of action potential, APA)及
所持續的時間(duration of action potential, APD)，並利用肌肉
等張收縮法來記錄心縮機械張力(mechanical tension, MT)的變化
情形。所有數據均用統計分析處理。
實驗結果顯示：注射雨傘節蛇毒3.2及6.4.mu.g/g b.w.一分鐘
後，大白鼠的SBP、DBP等有顯著降低的現象(P<0.01)，而其餘如SV、
MBF、HR、CO等各血流因子亦有減少的現象，約維持二分鐘後則逐漸
回升。以0.1-0.2mg/ml蛇毒水浴處理離體心房肌細胞時，其APA和HR
並無明顯的改變，但APD、PD50、PD75、PD90及MT等皆有顯著的增加
(P<0.05)；若改用0.2mg/ml蛇毒水浴處理離體心房肌細胞時，其上
述各項因子的變化情形大致類似，惟MT在30分鐘後反而逐漸下降。

Bungarotoxin was injected to study hemodynamic changes
and effects on cardiac cells of isolated atrium in rats.
Six hemodynamic factors: mean blood flow (MBF)、stroke volume
(SV)、pulstile blood flow (PBF)、systolic blood pressure
(SBP)、diastolic blood pressure (DBP) and heart rate (HR)
were investigated. The cardiac output (CO) values were
derived from data of SV and HR. To study effects of the venom
on the transmembrane potential of isolated atrial single cell,
the amplitude of action potential (APA) and duration of action
potential (APD) were investigated with an intracellular
recording method. The effect of the venom on the systolic
mechanical tension (MT) of myocardium was investigated with an
isotonical recording method. All data were analyzed with one-
way ANOVA.
In vivo study, the results showed that there were a
significant decreases (p<0.01) of SBP and DBP within 1 minute
following administration of bungarotoxin (3.2 and 6.4.mu.g/g
b.w.), and other factors (SV、MBF、HR、CO, etc.) were also
decreased. These hemodynamic factors were recovered gradually
after 2 minutes following treatment with venom. In vitro
study, there were no significant changes in APA and HR, but
APD、PD50、PD75、PD90 and MT were increased significantly
(p<0.05) following administration of bungarotoxin (0.1mg/ml,
bath). These factors were also increased following
administration of bungarotoxin (0.2mg/ml, bath) except MT.
The MT was decreased after 30 minutes following treatment
with venom.