肾上腺素是一种中枢神经系统内的生物胺,其浓度不到去甲肾上腺素浓度的5％。企图证实其为脑内一种神经介质的尝试,因其浓度极低而失败。合成肾上腺素的酶,苯乙醇胺N-甲基转移酶,已在散在的神经元,特别是延髓中的神经元中找到。近来有证据提示肾上腺素参与血压的中枢调节。此儿茶酚胺即将完全被证实为一种中枢神经系统的递质。 Epinephrine is a biogenic amine in the central nervous system that is less than 5% of the norepinephrine concentration. Attempts to prove that it is a neurotransmitter in the brain have failed because of its very low concentration. Synthetic epinephrine enzymes, phenylethanolamine N-methyltransferases, have been found in scattered neurons, particularly neurons in the medulla oblongata. Recently there is evidence that epinephrine is involved in central regulation of blood pressure. This catecholamine is about to be completely confirmed as a transmitter of the central nervous system.