Efedra; al.: Meertraübehen; ingl.: ephedra, joint to fir.
Aerial stems
Efedras is dióicos subshrubs with thin and angular stems and leaves reduced to grudges. The masculine flowers are grouped in yellowish amentos, the feminine flowers are reduced to ova surrounded by brácteas, red and fleshy when they mature.
Origin
The species that present/display interest are all of Asian origin, but the sort, that includes/understands several tens of species, is present in all the continents.
Chemical composition
The active components are arilalquilaminas whose structure is very similar to the one of catecholamines. Some consider them like alkaloids, whereas for other-due to that nitrogen is not comprising of heterociclo it is protoalcaloides. The drug also contains several flavonoides (flavonas and flavonoles, 0.3% in stems of And cynical, C-glucosil flavonas) [ 624.625 ], proantocianidoles [ 625 ] and polisacáridos.
Protoalcaloides. Its content, variable according to the species, is at the most of 3%. The majority component is almost always (-)-efedrina (1R, 2S) the 1-fenil 2-metilamino propan-1-ol. The different species also contain (+)-pseudoefedrina (1S, 2S), as well as the corresponding corresponding derivatives nor and metilados. These bases go accompanied by small amounts (10-5-10-4) of cyclical derivatives: 5-feniloxazolidinas and efedroxano (= (4S, 5R)-3, 4-dimetil 5-feniloxazolidona) [ 626 ].
Also, it is observed the presence of macrocyclical alkaloids, derivatives of the espermina: orantina in the 627 stems [ ], efedradinas B, C and D in the 628 roots [ ]. Within these last ones, also one has been able to isolate substances with hypotensile activity: derivatives of the histamina [ 629 ], proantocianidoles [ 630 and ref mentioned ] and a quaternary amino acid: the maoconina.
Farmacológicos data
The efedrina, structurally related to the adrenalin, causes a liberation of endogenous catecholamines of postganglionary likeable fibers: it is an indirect simpaticomimético. It accelerates the respiratory movements and it increases his intensity, it stimulates the automatism cardiac and she is vasoconstrictora. Its fort lipofilia allows him to cross the hemato-encephalic barrier and to exert important central effects: increase of the watch, diminution of the fatigue sensation. The obtained adrenérgica answer with a determined dose of efedrina, diminishes progressively of intensity until disappearing (phenomenon of taquifilaxia).
Although the efedrina and the pseudoefedrina have an identical broncodilatadora activity, the activity on the myocardium, the tension and the 631 S.N.C. of first is more important [ ]. In the case of the whole drug, the interference of the other components with the intestinal absorption of the fenetilaminas, modifies the action of these quantitatively, being its 632 action smoother and prolonged [ ]. The division of the metanólico extract of And intermediate sample that the main person in charge of the antiinflammatory activity is (+)-pseudoefedrina [ 633 ] and, to a lesser extent, the 626 efedroxano [ ], whose complex 634 pharmacology has been able to demonstrate [ ]. The polisacáridos ones are hipoglucemiantes.
Observations in the Man
All the properties of the efedrina, mentioned previously, have been observed in the man and taken advantage of in therapeutic. Their great variety of activities and the phenomenon of taquifilaxia has caused that their therapeutic indications are limited. In addition, it presents/displays numerous contraindications: prostate coronary insufficiency, hipertrofia, diabetes... Also it presents/displays medicamentosas interactions: with IMAO (Inhibiting of monoamino oxidasa), and with digitálicos. In most of habitual therapeutic indications (analéptico, antiasthmatic), the efedrina has been replaced by more manageable molecules. The efedrina does not lack toxicity. [ 635 has been described to a teratógena action in chicken embryo ]. For 5,000 years, the Chinese traditional medicine has been using the stems (má huáng) in the treatment of the asthma, the bronchitis and numerous affections. The Eastern tradition grants properties opposed to the underground organs.
Use
The different species from efedra at the present time, almost are not used for the extraction of efedrina. The efedrina and its salts are only used in "the pectoral" syrup formulation (broncodilatadores). This amine also comprises of the composition of dissolutions for used nasal instilaciones in case of rinorrea (vasoconstrictora). The prolonged use can originate the appearance of yatrogénica rinitis (and also, although more rarely, a iatrogénica arterial hypertension [ Dimitriou and col. ]). In the children, risk of depression of the S.N.C. and cardiovascular reactions can exist. The simpaticomimética activity of the stem provides used lipolíticas and anorexígenas properties in case of excess of weight. The criomolida drug does not produce any toxic manifestation in the tests of acute and subacute toxicity (3 g/kg, 300 and 600 mg/kg/día, 6 weeks, rat, to per you) [ 637 ].
The drug
The aerial stems of the different species from efedra fine, angular and are longitudinally fluted. The leaves, reduced to membranosas grudges, are inserted in pairs at level of the knots. The size of the entrenudos varies according to the species. Anatomically, winding his epidermis presents/displays estomas (not very noticeable) coming from the division of a cell mother (estomas haploqueílicos). The stems contain traqueidas punteadas that, by union of the cross-sectional scores, form almost open or open glasses. The log is of the type gimnospermo. The efedrina is analyzed by means of C.C.F. (but not difference of its isomers). In order to reveal the plates, ] is preferable to use ninhidrina instead of the general reagents of 323 alkaloids [. The H.P.I.C. very ] is adapted for the determination of 636 alkaloids [.
Bibliography
[ 624 ] Or PUREV, F. POSPISIL and Or MOTL
Flavonoids from sinica Ephedra Stapf.
Coll. Czech. Chem. Comm., 53, 3193-3196, 1988.
[ 625 ] K.R. MARKHAM
Distribution of flavonoids in the to lower plants and its evolution-
nary significance. In: The flavonoids: advances in research,
since 1980, J. B. HARBORNE, ed., London, Champman and Hall,
427-478, 1988.
[ 626 ] C. KONNO, T. TAGUCHI, M. TAMADA and H. HIKINO
Ephedroxane, anti-inflammatory principle of Ephedra herbs
Phytochemistry, 18, 697-698, 1979.
[ 627 ] M. TAMADA, K. ENDO, H. HIKINO and C. KABUTO.
Structure of ephedradine To, hypotensive principle of Ephedra
Roots
Tetrahedron Lett., 873, -876, 1979.
[ 628 ] H. HIKINO, M. OGATA and C. KONNO.
Structure of ephedradine D, to hypotensive principle of Ephedra
Roots
Heterocycles, 17, 155-158, 1982.
[ 629 ] H. HIKINO, And KISO, M. OGATA, C. KONNO, K. AISAKA,
H. KUBOTA, N. HIROSE and T. ISHIHARA
Pharmacological actions of analogues of feruloyl-histamine, an
imidazole alkaloid of Ephedra Roots.
It plants Med., 50, 478-480, 1984.
[ 630 ] And KASAHARA and H. HIKINO
Structure of mahuannin D, to hypotensive principle of Ephedra
Productos
Add to Favorite
