Ergot and ergotism

Barger, G. Ergot and Ergotism. I.omlon Gurney and Jackson, 1931. 

Barger, G. (1931) Ergot and ergotism, Gurney and Jackson, London. 

A base, formed by the bacterial degradation of histidine, and present in ergot and in many animal tissues, where it is liberated in response to injury and to antigen-antibody reactions. If injected it causes a condition of shock with dilatation of many blood vessels, loss of plasma from the capillaries to the tissues and a rapid fall in blood pressure. It is normally prepared from protein degradation products. 

The disease takes two different forms depending apparently on whether ergotoxia, the alkaloid ia ergot, attacks predomiaantiy the aervous or the circulatory system. The former coaditioa is characterized by severe coavulsive seizures the latter produces an iatense burning and itching of the skin called St. Anthony s Fire. 

There are currently two medicinally valuable alkaloids of commercial import obtained from ergot. Commercial production involves generation parasiticaHy on rye in the field or production in culture because a commercially useful synthesis is unavailable. The common technique today (65) is to grow the fungus in submerged culture. Clavicepspaspali (Stevens and Hall) is said to be more productive than C. purpurea (Fries). In this way, ergotamine (100,... 

Several chemical compounds may cause inflammation or constriction of the blood vessel wall (vasoconstriction). Ergot alkaloids at high doses cause constriction and thickening of the vessel wall. Allylamine may also induce constriction of coronary arteries, thickening of their smooth muscle walls, and a disease state that corresponds to coronary heart disease. The culprit is a toxic reactive metabolite of allylamine, acrolein, that binds covalently to nucleophilic groups of proteins and nucleic acids in the cardiac myocytes. 

Poisoning by ergot still occurs occasionally in countries where rye is extensively used as a food grain or where ergotised grain is liable to be fed to cattle and methods for its detection have been devised, but interest in the analysis of ergot centres chiefly on the estimation of the active alkaloids in the crude drug or its preparations. The methods used may... 

Isolation of Ergot Alkaloids. In the papers already quoted (refs. 6 to 19) the processes used for the isolation of the total alkaloids and the separation of the component bases are given to those may be added references to methods by other authors. There are also numerous patented processes, some of which are quoted in the following special sections. 

These urethanes and the amino-compounds described above do not isomerise or racemise like the lysergic acids and the ergot alkaloids, which is taken to indicate that the carboxyl group at C is an important factor in this reaction. 

Stoll, Hofmann and Petrzilka (1946) have also succeeded in obtaining dihydro-derivatives of this series (ergotinine type) of ergot alkaloids. Each of these bases yields two dihydro-derivatives, distinguished as isomerides I and II. Their chief characteristics are siunmarised in the following table —... 

Pharmacological Action. Certain of the simple amines and amino-acids found in ergot are pharmacologically active and have some influence on... 

Of the typical ergot alkaloids, six pairs f table, p. 526) are now known. The first five pairs are more complex in structure than the sixth pair, ergometrine and eigometrinine. 

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