Some alkaloids focus their range in a particular part of the body, although many of them can act on several fronts at once. Among those most affected would include:
nervous system: Some exert a stimulating role of the central nervous system as caffeine (especially coffee and tea), theobromine (cocoa) or strychnine (nux vomica), in very small doses is also seizure. Others, such as scopolamine of henbane (Hyoscyamus niger) have a calming role, hence they are used in medicine as sedatives. Morphine, an opium derivative latex extracted from the capsule of the opium poppy (Papaver somniferum) is the main sleeping pill. There are also some, such as aconitine (aconite) which, although they are initially stimulating, then they are paralyzing.
Muscles: Can affect all the muscles, producing violent spasms and very painful, such as strychnine, causing major upheavals that lead to death by suffocation or exhaustion. They can also act on certain specific muscles, causing them to dilate, as with scopolamine (henbane) responsible for the mydriasis or dilation of the pupil. Cause the opposite effect as others such as eserine containing the calabar bean (Physostigma venenosum) used in ophthalmology to contract the pupils of the eyes, or digitalis or digitalis from foxglove (Digitalis sp) acting on the heart muscle.
Digestive System: Some are very toxic to the digestive system, causing violent irritation of all gastric mucosal with typical manifestations such as diarrhea, vomiting, etc. Among these one of the most poisonous are the seeds of the castor bean (Ricinus communis) that contain the alkaloid ricinine, whose properties have been used as a purgative, but is extremely dangerous, since a couple of well-chewed seeds can be fatal to a child. Equally aggressive to the stomach is colchicine of autumn crocus (Colchicum autumnale). It should be mentioned those that attack the liver causing liver damage (cirrhosis, hepatitis, cancer, etc..), Such as the heliotrope cinoglisina (Heliotropium europaeum). Circulatory
: its effect on the blood circulation makes as reserpine from Rauwolfia vomitoria lowering blood pressure, so it is used to treat hypertension. Alkaloids that have an opposite effect would be, for example, the broom sparteine \u200b\u200b(Cytisis scoparius) hypertensive whose properties have been used to increase metabolism and promote the elimination of liquids. Respiratory
: In this section we alkaloids that have the property of dilating the bronchial tubes allowing an increase in breathing. Thus, the scoparin contained in the flowers of the broom (Cytisis scoparius) has been used to combat respiratory diseases. Also ephedrine, an alkaloid properties similar to the adrenaline produced by different species of the genus Ephedra has been used as a decongestant for the treatment of bronchial asthma and, in addition to possessing stimulant properties. The FDA (Food and Drug Directorate in USA) has recently banned its use. Many alkaloids that act on the respiratory system when they exceed the allowed doses produce respiratory arrest. Psychotropic
: Other alkaloids form part of the group called psychotropics, which are those that affect the mind, altering the perception. Among them we should mention:
Hallucinogens: they produce hallucinations or disturbances in thinking, feeling or perception in the form of distorted illusion of reality or perception of reality exist. Within this toxic as mescaline would as part of peyote (Lophophora williamsii), the cannabina of cannabis (Cannabis sativa) or harmaline of Syrian rue (Peganum harmala), the ergotoxine ergot (Claviceps purpurea) Amanita mushroom muscarine (muscarine Amanina). Narcotics
: alkaloids that cause narcosis, ie induce a dreamy state. Are used medicinally as analgesics, but so addictive that its use is regulated medically legal. Within this category would mainly opiates such as opium extracted from the latex of opium poppy (Papaver somniferum). Since it produces morphine, the primary analgesic. Codeine and heroin are derived from the latter. Stimulants
: produce a state of euphoria and well being. These would have known alkaloids such as cocaine extracted from coca leaves (coca Erythroxylon), widely used by Andean peoples as exhilarating to combat altitude sickness and allow better performance at work, besides many Other medicinal properties attributed to its users. Another alkaloid in this group is nicotine, which is obtained from snuff (Nicotiana tabacum) and most members of the Solanaceae family, also a stimulant that is addictive, and a deadly poison in low doses. Finally, we mention caffeine, an alkaloid present in plants such as coffee (Coffea arabica L.), tea (Camellia sinensis (L.) Kuntze), mate (Ilex paraguensis), cocoa (Theobroma cacao L.).
