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From very remote times, the indigenous inabitants of various parts of South America have been aware of the hallucinogenic properties of diverse species of the genus Piptadenia. The purpose of the present study is to bring out the salient facts concerning this botanical genus, which are of special importance today when pharmacotoxicology has reached what might be called the epoch of the "psychopharmacos ".

Synonyms

In the Caribbean Islands and in South America, piptadenias are known by various popular names, such as cebil, coboba, cohoba, cojoba, curupa, curuva, hataj, kurupa, kurupayara, niopo, nupa, ?opo, parica, vilca, yopo, yupa.

Historical and ethnographic data

Evidence of the use of Piptadenias exists from the time of the arrival of Christopher Columbus in the New World. The geographical area in which these plants are found embraces the West Indies, Brazil, Venezuela, Peru, Chile, Paraguay and the northern and central parts of Argentina. Throughout this vast zone the aborigines were familiar with the properties of Piptadenias, of which they made use by inhaling the powder obtained from the seeds. The variety of names which they bestowed on this plant can be gathered from the synonyms listed in the preceding paragraph.

Figure, 1, reproduced from the work by Cooper [1] , shows the distribution of these plants in South America.

Fernando Colon [2] reported that the aborigines kept the powder in the form of square "tablets" and inhaled it through a forked tube inserted in the nostrils.

Fray Bartolom? de Las Casas [3] , in the course of a very detailed account of cohoba, states that the natives used to hold meetings during which the chief inhaled powder made from the seeds. These meetings took place when matters of special importance to the tribe had to be discussed.

Francisco Lopez de Gomara [4] noted the same custom among the aborigines of Hispaniola where the bohitis (witch-doctors) also made use of the therapeutic properties of the powder.

Sotelo Narvaez [5] , in 1583, was probably the first person to describe the way in which the Comechingon Indians living in the Cordoba Mountains used powder made from cebil seeds.

FIGURE I

Distribution of Piptadenias in South America (areas marked in black), according to Cooper (1)

"E1 Orinoco Ilustrado" (The Orinoco Illustrated) by Padre Jos? Gumilla [6] contains the following passage on the Otomac Indians:

"... They have another dreadful way of getting drunk through the nose, using malignant powders called yupa, which drive them completely out of their minds so that, beside themselves, they seize any weapon to hand and if the women were not clever enough to stop them and tie them up, they would wreak cruel havoc every day: this is a terrible vice. They make these powders from the beans of the yupa plant, from which they get their name; by themselves they merely have the smell of strong tobacco; it is what is added to them by the work of the devil that causes the drunken fury. After eating some very big snails, which they find in the swamps they throw the shells into the fire and reduce them to quicklime, whiter than snow itself. They then mix this quicklime with the yupa, in equal quantities, and after grinding down the whole to a very fine powder, they obtain a mixture of such diabolical subtlety that the most hardened snuff-taker, so accustomed to tobacco that it no longer has any effect on him will, if he dips the tip of his finger in this powder and just puts his finger near to but without touching his nose, break out into a positive tempest of sneezing. The Saliva Indians and other tribes of whom I shall speak later, also take yupa; but as they are gentle, harmless and cowardly people, they do not become infuriated like the Otomacs who, for that very reason, have been, and still are, a terror to the Caribs, for they get fighting mad with yupa, wound themselves, and, full of blood and fury, go out to fight like raging tigers." *

Fray Ram?n Bueno [7] referring in his "Treatise" to the trade in beads carried on by the Otomac Indians says:

"They have another equally profitable trade - viz. dealing in curuva or ?opo with the Otomacs of Caracas province opposite. The tree does not grow in that province and at harvest time the Indians gather as much as they can and make it into medium-sized cakes, which they let the others have in exchange for shells, silver and glass beads, always keeping what they consider sufficient for their own use."

Padre Juan Rivero [8] in his history of the Missions in the Casanare plains and on the Orinoco and Meta Rivers, likewise makes numerous references to this trade.

In this text, the ancient orthograph has been respected in Spanish, and the paragraph from Father Gumilla's work has been reproduced literally.

According to Padre Pane [9] , the habit of inhaling powdered cohoba made the Indians so drunk that they would see their huts coming towards them and their companions walking with their feet in the air. When they became sober, they would relate what the Cemi (" Great Spirits ") had revealed, or announced to them.

Many explorers of the American continent have referred to the use of ?opo. One of the most famous, Baron Alexander von Humboldt, has given us in his travels [10] , an excellent description of this custom.

In his work on the Guarani Indians, Bertoni [11] speaks of the use made of kurupa, from the Amazon to Paraguay. The natives in this region were and still are in the habit of using powder made from the seeds of the tree known to them as kurupayara. The Omagua Indians also used to take this drug, as de la Condamine [12] observed:

"The Omaguas make considerable use of two kinds of plant: one, which the Spaniards call Floripondia, and the other, which is known in the Omagua tongue as curupa; both are purgatives. These peoples get drunk on these plants, the intoxication lasting twenty-four hours, and while under their influence they have very strange visions. They also take curupa in powdered form, as we take tobacco, but more ostentatiously. They use a hollow forked reed, in the shape of a letter Y, inserting each branch of the fork into one of the nostrils; this operation, followed by a violent intake of breath obliges them to make a grimace that seems very ridiculous in the eyes of Europeans, who like to compare everything with their own customs."

Equally valuable data have been provided by the well-known Venezuelan writer Lisandro Alvarado [13] .

Among the many authors who have dealt with Pip-tadenias, mention should also be made of Boman [14] , Koch-Gruenberg [15] and Padre Lozano [16] who have described their use among the Indians in Bolivia, Brazil and in the Orinoco zone.

For many years little interest was shown in this subject but, in 1948, we were consulted about the matter by the Pan-American Public Health Office. Our report on it was published in the Public Health Offices Bulletin [17] . Later in the same year and subsequently, in 1956, we published further papers on the subject [18] [19] .

Ethnographers who have studied the use of hataj include Elisabeth Dijour [20] and Enrique Palavecinu, Director of the Tucuman Ethnographic Museum [21] . Both authors have described ceremonies among the Bazan-Coronel Indians who resort to mass magic in order to drive away certain diseases, or implore help from the spirits. During these ceremonies the tribal witch-doctors inhale powder made from the seeds and scatter some of it on the ground for the spirits of the deceased witch-doctors invited to attend the functions. In his interesting study on the same topic, Lazaro Flury [22] has related how on one occasion an E1 Pintado chief told him "The man seems to be flying ", thereby revealing the motory and psychic excitative effects of the drug.

According to Pittier [23] , the word niopo is current in South Venezuela, yopo in the Upper Orinoco area, and cojoba in North Venezuela and Haiti. Gumilla [6] always uses the name yupa. According to Humboldt [10] , the Otomac Indians called it niopo and in the Maypure dialect, nupa. The same author tells us that the missionaries knew it as nopo. As we have already seen Fray Ramon Bueno [7] speaks of curuvaor ?opo.

Botanical data

Willdenow [24] classifies the plant as an Inga. This classification was disputed by Humboldt (10), who attributed it to an oversight on the part of Willdenow, with the result that in the work published by C. S. Kunth [25] the plant appears as an Acacia. In this work, entitled " Synopsis Plantarum Aequinoctialium Orbis Novi", which contains all the plants studied by Humboldt and Bonpland in the New World, we find it described as follows:

A. inermis; foliis bipinnatis; pinnis sub 23-jugis; foliolis 50-70 jugis; linearibus, subfalcatis, acutis, obsolete uninerviis, membranaceis, glabris, ciliatis; glandula supra basim petioli et inter summum pinnarum par; leguminibus linearibus rostratis.

Ex seminibus tritis calci vivae admixtis fit tabacum nobile quo Indi Otomacos et Guajibos dicti utuntur.

Today the scientific name given to the plant is Piptadenia peregrina Benth. of the family Mimosaceae.

"A medium-sized tree with most beautiful foliage, the leaves having from 15 to 30 pinnae, each bearing from 30 to 80 tiny leaflets; the flowers, in pedunculate capitula, are white; the legume is up to 15 cm. long and from 1.3 to 1.7 cm. wide. The wood is very hard, composed of knotty fibres and difficult to work. It is curious to find that this tree has the same native name of cojobaor cohoba in Haiti and in Venezuela, and that in both countries the aborigines were accustomed in the past, as they still are in parts of Venezuela and in the adjoining areas of Colombia and Brazil, to get drunk by inhaling the powder obtained from grinding its seeds, which provokes a kind of temporary madness."

The above description may be supplemented by the observations of Llewellyn Williams in his "Exploraciones Bot?nicas en la Guayana Venezolana" [26] :

"A tree 12 m. or more in height with a spreading tuft; the trunk is usually crooked, measures up to 35 cm. or more in diameter and is more or less free of branches till halfway up; the bark is thick and rough; the leaflets are tiny, linear and pinnated; the flowers, yellowish white in colour, form dense clusters; the legume reaches as much as 16 cm. long and is from 1.5 to 2 cm wide; the wood is hard and strong with dark duramen, but the dimensions are generally small and it is therefore of little practical use. The bark is rich in tanning principle. This tree abounds in scattered woodlands and on the savannas and the fringes of the jungle bordering the plains.

Hataj or cebil has been given the scientific name of Piptadenia macrocarpa Benth.

Figure II has been made available by courtesy of Professor Tob?as Lasser, Director of the Caracas Botanical Institute. It represents the inflorescence, a branch, leaves and legume (in the form of a pod) of Piptadenia peregrina Benth.

How the drug is obtained. Special preparation and mode of use

Baron Alexander von Humboldt [10] has left us an account, which we give below, of the method of obtaining and preparing the drug attributed by him to the Otomac Indians.

"... They also reach a special state of drunkenness, which might be called madness, by using the niopo powder (in maypure, nupa), (the missionaries call it nopo). They collect the long shells of a species of mimosa to which we have given the name Acacia Niopo; they break them up, moisten them and leave them ferment. When the softened seeds begin to turn black, they knead them into a paste; after mixing this with yuca flour and lime obtained from the shells of a kind of Ampularia snail, they heat the dough over a very hot fire on a hardwood grid. The hardened dough is made into small cakes. Before the drug is taken, these are reduced to very fine powder and placed on a plate from 5" to 6" long. The Otomac Indian holds this plate, which has a handle, in his right hand while he breathes in the niopo through a forked bird's bone, putting the ends in his nose. The bone, without which the Otomac would not think it possible to take this kind of snuff, is about 7" long; it seemed to me to be the shank of a big wading-bird. I have sent some niopo and all this strange apparatus to Mr. de Fourcroy in Paris. Niopo is so stimulating that for anyone not used to it the smallest quantities provoke violent sneezing..."

FIGURE II

Piptadenia peregrina Benth .(Mimosaceae)

1. Inflorescence 2. Branch with leaves 3. Legume (in form of pod) (Figure reproduced by permission of Professor Tobias Lasser, Director of the Botanical Institute, Caracas, Venezuela)

FIGURE III

Basket made of woven palm leaves, wooden plate, mortar and inhaler used by the Guahibo Indians.

( From the author's private collection)

"... Yopo or yupa is a kind of snuff extracted from the seeds of a species of Gwana acacia, also called yopo or niopo. The legumes are gathered, broken up, moistened and left to ferment."

At the present time, various Indian tribes still take ?opo, a vice they have inherited from their forebears. The most usual procedure is as follows: the dried seeds of Piptadenia peregrina Benth are finely ground and the powder thus obtained is mixed with another produced by crushing the shells of a variety of snail, generally Ampularia. As reported by Humboldt, huca flour is certainly added, although some Indians maintain that banana flour is preferable. It is also said that the fat extracted from the snails is used for cooking the dough. After this cooking process, small cakes are made and these are pounded with a mortar on a special plate to provide the powder, which is inhaled like snuff. The wooden plate, shown in figure III, is flat and has a slightly raised rim; it is ovaloid in shape and measures 11 cm x 9.5 cm. It has a flat handle 5.5 cm long and about 1 cm thick, which is 6 cm wide where it joins the plate, and 10 cm wide at the farther end.

FIGURE IV

(1) Wooden plate; (2) mortar; (3) inhaler.Implements used by the Guahibo Indians.

(From the author's private collection)

The mortar consists of two small tapered blocks joined at their smaller end. It is 5.5 cm long, 3 cm wide and 2.5 cm thick. Figures III and IV show all the implements used by the Guahibo Indians. The inhaler is made from a bone and appears in fact, to be a forked bone of a large wading-bird (probably a Jabiru); it is hollow and bound at the fork with waxed cord; the lower end, to be immersed in the powder, is bevelled; the upper ends are tipped with small perforated balls (two dried berries) which are applied to the nasal orifices. A bird's feather is used to keep the inhaling tube clear. The powder, prepared as described above, is of a reddish-brown colour, thick and a strong irritant.

All this arsenal of equipment is carried about in a small basket made of woven palm leaves.

The methods used for inhaling the drug vary with the region. For example, the Guaica Indians do not use the same implements as those described above. These natives use a long tube, the farther end of which is inserted in the nostril of the Indian who is going to inhale the powder, while an assistant applies his mouth to the other end and blows the powder vigorously through the tube.

Figures V and VI taken from the Boletin Indigenista Venezolano[27] , give an idea of this curious mode of inhaling ?opo.

In an excellent study of the Yabarana Indians, Johannes Wilbert [28] has also described the way members of this tribe take powdered Piptadenia. According to this author, the Yabarana Indians use the same methods as the Guahibos, described above.

FIGURE V

Guaica Indian inhaling ?opo powder blown through a tube by one of his companions.

(O. Zerries, ref. No. 27)

Data concerning the chemical composition of the drug

The chemical analysis of the plant has been carried out by Fisch, Johnson, and Homing [29] . These sciettists have studied the composition of the seeds and legumes (pods) of two species, Piptadenia peregrina Benth, and Piptadenia macrocarpa Benth.

FIGURE VI

Guaica witch doctor; after inhaling ?opo powder, he begins to invoke the spirits.

(O. Zerries, ref. No.27)

The seeds and pods of both species were found to contain 4 indole bases. The pods contain N.N-dimethyltryptamine and the seeds bufotenin, bufotenin oxide and oxide of N.N.-dimethyltryptamine.

The seeds of the species macrospora were also found to contain a 5-hydroxyindole base of unknown structure.

The above-mentioned researchers identified these components, isolating them by paper chromatography and comparing them with test samples covering data relating to the Rf, the ultra-violet spectra and the fluorescence analysis.

Piptadenia colubrina contains the same active principles as the species mentioned above.

All research workers who have studied the effects produced by these plants agree in attributing them to the presence of bufotenin and its oxide, of the alkyl derivatives of tryptamine and, among the latter, particularly of N.N-dimethyltryptamine and its oxide. Actually, from the point of view of their chemical structure, all these active principles are closely related to serotonin.

Figure 7 shows the chemical structure of tryptamine, serotonin, bufotenin and N.N-dimethyltryptamine (DMT), and indicates quite clearly the close relation between all these substances.

Pharmacological and Toxicological Data

Humboldt [10] appears to attach greater importance to the presence in the compound of freshly calcined lime than to the active principles of the plant, as can be seen from the following passage:

"... It is not to be believed that the niopo acacia pods are the chief cause of the stimulating effects of the snuff used by the Otomac Indians. These effects are due to the freshly calcined lime."

However, the arguments with which this author supports his opinion are highly debatable; the fact that natives of the Popoyan Andes and the Goajiro Indians of the Lake Maracaibo district eat lime as a stimulant in order to increase the secretion of saliva and the gastric juices does not in any way mean that lime should be regarded as the active agent in the drug, particularly as the real effect of ?opo is very far from being that of a mere stimulant of secretions.

De la Condamine [12] has stated that the Omagua Indians of the Upper Mara?on region also use a plate and inhaler to take curupa powder. Little doubt remains today that curupa and ?opo are very similar, not to say identical.

FIGURE VII

According to the classical descriptions, ?opo might be said to have a two-phase action. During the initial period, or phase, the drug has a stimulating effect, producing great excitement in the subject and the onset of hallucinatory delirium. The symptoms vary widely according to the personality of the subject; the use and abuse of this drug, as is the case with many others such as alcohol, cannabis, etc. may produce very different effects according to the psychological characteristics of the person taking it. It is interesting to note that a primitive and barbarous tribe, such as the warlike Otomacs, use ?opo as a stimulant before battle, whereas peaceful tribes like the Guahibos, take the drug for different purposes.

During the second phase, sleepiness is followed, according to most observers, by complete hypnosis. The drug in short, creates a very special kind of drunkenness accompanied by loss of reasoning power and finally by unconsciousness lasting for the duration of the hypnosis.

In preliminary experiments carried out in our laboratory in 1947 and 1948, we tested the action of the compound as used by the Guahibo Indians. To ensure adequate penetration of the prepared powder, we used a special device which has been described elsewhere (18 and 19). Using this device we administered the powder to mice and rats. The results obtained from our experiments can be summarized as follows:

In 1956, Raymond Hamet [31] made a study of the pharmacological effects of an extract of Piptadenia peregrina.

It has now been demonstrated that the effects produced by the various extracts and preparations of these plants are due to the presence of bufotenin and the derivatives of tryptamine (chiefly dimethyltryptamine, or DMT).

A group of research workers at the Budapest Central Institute for Nervous and Mental Diseases has published a series of studies of great interest in this field. Among these, the following deserve special mention:

In 1956, Sai-Hal?sz [32] submitted to the third International "Rorschach" Congress, held in Rome, his observations on certain aspects of the Rorschach test during experimental psychosis produced by DMT.

In the same year, St. Sz?ra [33] , another member of the group, published an initial report, supplemented a year later by a further paper, dealing with the effects of various tryptamine derivatives [34] .

In 1957, Sz?ra, in collaboration with B?sz?rm?nyi and Sai-Hal?sz [35] described the results of further experiments in the same field.

In 1959, Sai-Hal?sz and Endr?czy [36] studied the effects of tryptamine derivatives on the behaviour of a dog under the influence of stimuli applied to the brain stem. These authors were also able to show that the intramuscular injection of DMT into human patients in doses of 0.8 mg per kg of body weight produced very marked psychotic effects, which began from four to six minutes after the injection and lasted from forty to fifty minutes. According to them: "The experimental psychosis is characterized by brilliantly coloured hallucinations and accompanied by very marked vagal symptoms, such as mydriasis, hypertension, dyspnoea and frequently by anxiety ". For the experiments carried out by them on dogs the animals had to be specially trained until they had developed a conditioned reflex to food; special electrodes were inserted to stimulate different cerebral areas. The results of this very interesting study were published by Elsevier in 1959, under the title: "NeuroPsychopharmacology ", which supplemented the work published by Sai-Hal?isz, Brunecker and Sz?ra [37] a year earlier.

With regard to the effects produced by bufotenin, the following studies should be mentioned:

In 1955, Evarts and his collaborators [38] described the psychoto-mimetic effects of bufotenin, (dimethylamino-5-hydroxytryptamine).

In the same year Fabing and Hawkins [40] published an interesting paper, which was followed by another by Woods and his collaborators [41] .

Later, in 1959, Costa and his collaborators [42] studied the effects of the intravenous injection of bufotenin and Courvoisier and Leau [43] analyzed the protective action of parenterally administered hydroxy-5-triyptamine (5HT) against bronchitis provoked in guinea pigs by the same substance applied in aerosols. At the same time, these scientists analyzed the protective action of bufotenin.

In one of his studies on psychoto-mimetic drugs, Plutarco Naranjo [44] has summarized the principal effects of bufotenin and DMT. The following data are reproduced from his work:

Psychoto-mimetie effects

Drug	Via *	Dose(mg)	Begin (min)	Maximum effect	Total duration (hours)	References: **
Bufotenin	I.M.	10-20	10-15	?a	1-3	No. 40
	I.V.	6-8	2-3	?h	1	No. 40
				8-10 m
N.N.-Dimethyl-Trypta-mine (DMT	Or.	150	-	-	-
	I.M.	50-80	10-20	20-30	?-1	No. 34
				min

In short, it can be said that the most striking effects of these drugs are the following:

Data concerning the mechanics of the drug's action

It is not possible to claim that the mode of action of the drug has been completely clarified. However, certain data have been obtained which can be considered of special interest. Before summarizing these data we would recall the excellent general review of the subject by Turner and Merlis [45] published in 1959.

Many researchers in this field have drawn attention to the possibility that bufotenin and DMT may in some way interfere with the metabolism of serotonin (5-hydroxytryptamine), by inhibitory action through competition, or by blocking certain enzymatic systems, etc.

It has been proved that serotonin is found chiefly in the diencephalic nuclei, in the "limbic system" and in the "reticular ascendant" system. Norepinephrin is also found in these formations and the important role of acetylcholine as a chemical mediator not only in the peripheric, but also in the central, synapses should not be overlooked. It has therefore been assumed that the normal transmission of nervous impulses through the systems mentioned above depends not only on the concentration of serotonin and norepinephrin, but also on the maintenance of a possible balance between these and acetylcholine; upsetting this balance might perhaps give rise to psychoto-mimetic effects.

Raymond Hamet [46] is of the opinion that bufotenin can liberate catecholamines from their peripheric deposits. This finding gave Costa and his collaborators [42] the idea that the same effect might be produced within the brain stem.

Woods and his collaborators [41] think that bufotenin when it reaches the suprarenal glands, might possibly liberate catecholamines from the medullary part of the glands.

There is much that is still obscure about the complicated mechanics of the action of the components of the ancient drug used by the South American Indians. The present paper has been written with the object of keeping alive the interest of researchers in this very promising field.

Final considerations regarding the etiology of the custom of taking piptadenia

The chief causes and motives which lead various primitive tribes to make use of powdered piptadenia seeds would appear to be the following:

Another aspect of the question which should not be overlooked is the association of the drug with other toxic substances, especially alcohol and tobacco. In some regions the use of this drug is also associated with that of ca?-p? ( Banisteria ca?-p? Spruce), another powerful hallucinogenic agent.

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