THE opinion has been advanced that acetylcholine acts in the heart not only as the mediator of the vagus nerve but also as the so-called local hormone in local extraneural regulation of heart activity ...

RESERPINE, guanethidine and syrosingopine, which are potent hypotensive drugs, have been shown to produce side effects suggestive of increased parasympathetic activity. Some of these effects, such as ...

Scientists are reporting the first compelling evidence in people that cognitive training can boost levels of a brain chemical that typically declines with age. A 10-week study of people 65 or older ...