Bloom F, Segal D, Ling N, Guillemin R
Science. 1976 Nov 5;194(4265):630-2. doi: 10.1126/science.185694.
The endogenous morphinomimetic brain peptides Met5-enkephalin and alpha-, beta-, and gamma-endorphins have been evaluated in rats after intracerebrospinal fluid injection. beta-Endorphin produces marked, prolonged muscular rigidity and immobility similar to a catatonic state, counteracted by the opiate antagonist naloxone; this effect occurs at molar doses 1/100 to 1/400 that at which the other peptides or morphine block the response to painful stimuli. All peptides evoked dose-related, naloxone-reversible, wet-dog shakes in rats that had not been exposed to drugs. beta-Endorphin produced hypothermia, whereas gamma-endorphin produced hyperthermia. Such potent and divergent responses to naturally occurring subtances suggest that alterations in their homeostatic regulation could have etiological significance in mental illness.
内源性类吗啡脑肽甲硫氨酸脑啡肽以及α、β和γ内啡肽，已在大鼠经脑脊髓液注射后进行了评估。β内啡肽会产生明显且持久的肌肉强直和不动，类似于紧张症状态，可被阿片拮抗剂纳洛酮抵消；这种效应出现在摩尔剂量为其他肽类或吗啡阻断对疼痛刺激反应剂量的1/100至1/400时。所有肽类在未接触过药物的大鼠中均诱发了剂量相关、纳洛酮可逆的湿狗样抖动。β内啡肽导致体温过低，而γ内啡肽导致体温过高。对天然物质如此强大且不同的反应表明，其稳态调节的改变可能在精神疾病中具有病因学意义。
