Brisse B
Fortschr Med. 1976 Aug 12;94(22-23):1233-7.
Metabolic studies on isolated rat organs showed that vanillyl mandelic acid (VMA) is dehydrogenated by liver homogenate and suspension of pseudomonas fluorescens. In the 100000 g supernatant fraction of homogenated rat kidneys enzymatic activity was sufficient for kinetic studies and the examination of substrate specificity, pH dependence and changes with age and sex of rats. Norepinephrine secretion and resorption may be influenced by antiarrhythmic drugs in vivo: after lidocaine, there was no change of the tyramine dependend norepinephrine depletion of rat hearts, Verapamil inhibited the uptake of norepinephrine by rat hearts. Immobilisation of the animals led to a significant decrease in the myocardial levels for norepinephrine and epinephrine, which was antagonised by recreation of 24 hours. Adumbran prevented the catecholamine depletion, so that the influence of the limbic system may be important for the mediation of sympathetic stimuli.
Emotional stress was shown to lead to an elevated plasma level of norepinephrine, cortisole and free fatty acids. In patients undergoing surgery, the application of Valium and Fortral inhibited these stress reactions. After physical stress, which did not lead to significant changes of the catecholamine level in plasma of healthy volunteers, there was an elevated norepinephrine plasma level in patients with cardiac failure, which could be prevented by different antiarrhythmic drugs. The excretion of norepinephrine and VMA of these patients was also increased. It was shown, that sinus rate rose according to norepinephrine levels in plasma in this group, which was contrary to the behaviour of healthy volunteers, showing neither a norepinephrine overflow nor increased heart rate. In patients with atrial fibrillation, AV-conduction also increased with elevated norepinephrine levels in plasma. There was, however, no direct correlation. Determination of the cardiac AV-difference of plasma-norepinephrine levels showed a cardiac catecholamine overflow, which could be inhibited by specific and nonspecific antiarrhythmic drugs (Verapamil, Practolol). In studies of catecholamine and glucocorticoid metabolism, no significant difference of catecholamine and VMA could be determined in patients with normal blood pressure and arterial hypertension. There was, however, a tendency to increased values in patients of the last group. In postural hypotension, plasma levels and urinary excretion of catecholamines were decreased and showed no variation after physical stress in orthostasis and after nicotine. In patients with tumors of the adrenal cortex and medulla, a close relation of the disturbance in catecholamine and corticoid metabolism was revealed.
对离体大鼠器官的代谢研究表明，香草扁桃酸（VMA）可被肝匀浆和荧光假单胞菌悬液脱氢。在大鼠肾脏匀浆的100000g上清液组分中，酶活性足以进行动力学研究以及底物特异性、pH依赖性以及大鼠年龄和性别的变化研究。体内抗心律失常药物可能会影响去甲肾上腺素的分泌和重吸收：利多卡因给药后，大鼠心脏中酪胺依赖性去甲肾上腺素耗竭无变化，维拉帕米抑制大鼠心脏对去甲肾上腺素的摄取。动物固定导致心肌中去甲肾上腺素和肾上腺素水平显著降低，24小时恢复后这种降低被拮抗。阿杜姆布兰可防止儿茶酚胺耗竭，因此边缘系统的影响可能对交感神经刺激的介导很重要。
情绪应激被证明会导致血浆去甲肾上腺素、皮质醇和游离脂肪酸水平升高。在接受手术的患者中，应用安定和福他乐可抑制这些应激反应。在健康志愿者血浆中儿茶酚胺水平未发生显著变化的身体应激后，心力衰竭患者的血浆去甲肾上腺素水平升高，不同的抗心律失常药物可预防这种情况。这些患者的去甲肾上腺素和VMA排泄也增加。结果表明，该组患者的窦性心率随血浆去甲肾上腺素水平升高而上升，这与健康志愿者的行为相反，健康志愿者既无去甲肾上腺素溢出也无心率增加。在心房颤动患者中，房室传导也随血浆去甲肾上腺素水平升高而增加。然而，两者无直接相关性。血浆去甲肾上腺素水平的心脏房室差异测定显示存在心脏儿茶酚胺溢出，特异性和非特异性抗心律失常药物（维拉帕米、心得宁）可抑制这种溢出。在儿茶酚胺和糖皮质激素代谢研究中，血压正常和动脉高血压患者的儿茶酚胺和VMA无显著差异。然而，后一组患者的值有升高趋势。在体位性低血压中，儿茶酚胺的血浆水平和尿排泄减少，在直立位身体应激后和尼古丁作用后无变化。在肾上腺皮质和髓质肿瘤患者中，揭示了儿茶酚胺和皮质激素代谢紊乱之间的密切关系。
