Leitner L M
Univ. P.-Sabatier, Fac. Méd., UA CNRS 649, Toulouse, France.
Adv Exp Med Biol. 1993;337:183-90. doi: 10.1007/978-1-4615-2966-8_26.
Dopamine (DA) and noradrenaline (NA) were measured in the rabbit carotid body (CB) in vitro bv HPLC-ED under the following experimental conditions: 1h superfusion in normoxic, hypoxic (10% O2 in N2) or hypercapnic (8% CO2, 20% O2, 72% N2) medium, 5h superfusion in normoxia or hypoxia. The contents of DA and NA were decreased by hypoxia and hypercapnia after 1 h and 5h indicating a possible DA and NA secretion. Under the same experimental conditions synthesis of DA and NA and catabolism of DA were studied with enzymatic inhibition of tyrosine hydroxylase and monoamine oxidase (MAO) respectively. In hypoxia (1 h and 5h) the rate constant of DA synthesis was the same as in normoxia; however NA synthesis was decreased after 1 h hypoxia. On the contrary, hypercapnia, appeared to be a very effective stimulus of DA and NA synthesis.
在以下实验条件下,通过高效液相色谱 - 电化学检测法(HPLC - ED)在体外测定兔颈动脉体(CB)中的多巴胺(DA)和去甲肾上腺素(NA):在常氧、低氧(氮气中10% O₂)或高碳酸血症(8% CO₂、20% O₂、72% N₂)培养基中进行1小时灌注,在常氧或低氧条件下进行5小时灌注。1小时和5小时后,低氧和高碳酸血症使DA和NA含量降低,表明可能存在DA和NA分泌。在相同实验条件下,分别通过酪氨酸羟化酶和单胺氧化酶(MAO)的酶抑制作用研究了DA和NA的合成以及DA的分解代谢。在低氧(1小时和5小时)条件下,DA合成的速率常数与常氧时相同;然而,低氧1小时后NA合成减少。相反,高碳酸血症似乎是DA和NA合成的非常有效的刺激因素。