十余年来科学家已知人体可以制造吗啡样天然鸦片类物质,如内啡肽。这些常在紧张状态下释放的化学物质能暂时减弱人体对疼痛的敏感性。但印第安纳州西拉斐特Purdue大学的George K W Yim等发现,内啡肽似乎具有另一种功能,从化学上将紧张与心脏病联系起来。在小鼠和大鼠的研究中,他们发现某种尚未鉴定的内啡肽对处于紧张状态下动物血清中 For more than a decade scientists have known that the body can produce morphine-like natural opiates, such as endorphins. These chemicals, which are often released under stress, temporarily weaken the body’s sensitivity to pain. But George K Wim et al., Of Purdue University in West Lafayette, Indiana, find that endorphins seem to have another function that chemically links stress with heart disease. In the studies of mice and rats, they found that certain unidentified endorphins were found in animal serum under stress