The direct beneficial effects of the ginseng herb on many organs and glands in the human body has been identified in various tests by clinical researchers that measure the benefits of various chemical compounds in the herb. However, the exact biochemical basis for most of these effects the herbal constituents have on the body is still a mystery and requires further investigation. Current scientific know how is still insufficient to gauge all the potential and actual nature of the diverse chemical constituents in the ginseng herb, it is still not possible to probe and get a precise knowledge of their functions and map out all their effects. That so many physiological effects are due to just one herb, sometimes does seem unlikely and even impossible, this is one reason that the ginseng is often called the wonder herb in the literature. The effects of ginseng on hormones may provide a clue, and the entire biochemical explanation for the benefits of the herb may be at the level of regulation of hormones and their role in the human body.
The connection between the functioning of the adrenal glands and the ginseng has been studied thoroughly and is well documented in the literature. The resistance of the body to stress is increased by taking ginseng and this has been proven in animal tests where animals that had their adrenal glands removed could get no benefit from administrations of ginseng. Ginseng may have an indirect regulatory action on the adrenals through the hypothalamus, or it could be acting directly on the adrenals in controlling stress in the body - but the fact that it has a controlling influence over the adrenals is not disputed in the literature. One of the main roles of ginseng in normal animals facing stress is the stimulation of the biochemical production of stress hormones in large amounts, helping the body to cope with stress immediately. The herb has a very strong action in this regard, for example, the production of stress hormones in the adrenals stops immediately when the stress goes away in animals that are not given ginseng, but this is not the case in animals given ginseng which continue to produce hormones for some time even when the stress disappears. The adrenals of ginseng administered test animals seem to conserve the produced stress hormones after the passage of the stress inducing factor and seem to prolong endurance in the body. The adrenals of animals treated with ginseng and other adaptogens reacts better to stressful situation and is more adaptable in the event of trauma, in general, the efficiency of the adrenals is increased by the ginseng and other adaptogens given during tests. Scientist have still not been able to identify the exact pathway of action and if these biochemical effects of the herb are solely felt by the adrenal glands, or if the hypothalamus and the pituitary are also affected in some way.
The role of the ginseng in sensitizing the hypothalamus to increase its efficiency and performance has been possibly revealed in the experiment of a ginseng researcher from Great Britain. The direct action of ginseng on the pituitary and the adrenal glands and its effects on the sex glands that are under the regulation of the hypothalamus could be revealed if this experimental results are proven to be true, ginseng then will also be indirectly connected and will be presumed to have an effect on the target organ tissues that these glands act on and regulate in the physiology of the body. During one study, all possibility of stress hormones being produced by adrenal glands and ovaries in laboratory rats were eliminated when these structures were removed from the test animals. These laboratory rats were then separated into two testing groups, one group was given only placebos for eight days, while the other group of test rats received ginseng for the same duration. The main stress hormone in mammals, called corticosterone was then injected into all these animals following the dosage with placebos and ginseng. In order to know, where exactly in the body the corticosterone ended up, the researchers chemically "tagged" the hormone before injecting them into the test animals. Compared to the placebo group of test rats, the rats that were given ginseng, showed corticosterone deposition of more than seven times as much in the brain regions surrounding the hypothalamus - thus ginseng is directly responsible in these animals in how stress hormones are handled. The balancing action of the hypothalamus to hormone levels in the body is apparent and in all normal bodies, the hypothalamic area operates a feedback loop for the stress hormone corticosterone and other hormones. Once the elevated levels of theses hormones are detected by the brain, a balancing biochemical mechanism comes into play and the levels of hormones are regulated in this way. The effectiveness of the corticosterone in combating stress may be increased by the ginseng because the herb may sensitize the hypothalamus to the operation of this biochemical feedback loop in the brain. Brain efficiency of people on ginseng is believed to be greater, because the herb acts in "priming" the hypothalamus, resulting in the initiation of hormonal secretions that lead to greater efficiency in brain functioning, according to the studies of one ginseng researcher.