儿茶酚胺类激素对华贵栉孔扇贝循环生理的影响

Effects of Catecholamines on Circulatory Physiology of Chlamys nobilis

【目的】探究儿茶酚胺类激素对华贵栉孔扇贝(Chlamys nobilis)循环生理的影响,为贝类应对环境胁迫的生理响应研究提供基础。【方法】将0.2、1.0、2.0μmol/L的儿茶酚胺类激素(多巴胺、去甲肾上腺素、肾上腺素)注射到华贵栉孔扇贝体内,运用多普勒超声成像技术实时监测扇贝在0、5、20、40、60、180、300 min时的心率、舒张末期速度、收缩峰值速度、血流量等循环生理指标变化情况。【结果】注射0.2μmol/L的多巴胺和肾上腺素后,扇贝的心率相对变化率与海水对照组之间均无显著差异(P> 0.05),而舒张末期速度、收缩峰值速度、血流量分别在注射后20、40 min显著高于对照组(P <0.05);注射0.2μmol/L的去甲肾上腺素后,仅舒张末期速度在注射后5 min显著高于对照组(P <0.05);注射1.0μmol/L的儿茶酚胺类激素后,扇贝各循环生理指标的相对变化率平均值在40 min前低于对照组,在60 min时高于对照组;注射2.0μmol/L的儿茶酚胺类激素后,扇贝各循环生理指标的相对变化率平均值在40 min前均低于对照组且为负值,在180 min时高于海水对照组。【结论】低浓度(0.2μmol/L)的儿茶酚胺类激素对扇贝的部分循环生理指标起兴奋作用;中、高浓度(1.0、2.0μmol/L)的儿茶酚胺类激素对扇贝的循环生理指标有先抑制后兴奋的双相调节作用,且浓度越高抑制效果越明显。

【Objective】To explore the effects of catecholamines on the circulatory physiology of Chlamys nobilis,and set a basis for the research on the physiological response of shellfish to environmental stress.【Method】Three different concentrations(0.2,1.0,2.0μmol/L)of catecholamines(dopamine(DA),norepinephrine(NE),epinephrine(E))were injected into the scallop,the changes of circulatory physiological indicators(heart rate,end-diastolic velocity,peak systolic velocity,and blood flow volume)of scallop at different time(0,5,20,40,60,180 and 300 min)was monitored by Doppler ultrasound imaging technology.【Result】After injection of 0.2μmol/L of DA and E,there was no significant difference in the relative change rate of heart rate between the low concentration group(0.2μmol/L)and the seawater control group,while the relative change rate of other circulatory physiological indicators reached the maximum values 20 min and 40 min after injection, which were significantly higher than those of the control group (P < 0.05). After injection of 0.2 μmol/L of NE, only the end-diastolic velocity reached the maximum value 5 min after injection, which was significantly higher than that of the control group (P < 0.05). After injection of 1.0 μmol/L of catecholamines, the relative change rates of circulatory physiological indexes of scallops were lower than those in control group before 40 min, but higher after 60 min. Injected with 2.0 μmol/L catecholamines, scallops had lower and negative relative rate of change in each circulatory physiological index than those in control group before 40 min, and higher than the control group at 180 min. 【Conclusion】Low concentration (0.2 μmol/L) of catecholamine has excitatory effects on part of the circulatory physiological indicators of scallops. Medium and high concentrations (1.0 and 2.0 μmol/L) of catecholamines can generate bidirectional effect on circulatory physiological indexes, and the higher the concentration, the more obvious the inhibitory effect.