Ustilago. Ustilago maydis Leveillé (Nat. Ord. Fungi) grows upon Zea mays Linné (Nat. Ord. Graminaceae).

Extractum Ustilaginis Maydis Fluidum

Fluid extract of ustilago. Dose, τη x — 3 j-

Composition

An active principle—ustilagine—has been lately found, and some of the ingredients existing in ergot have been detected, as secaline so called, and trimethylamine; but the latter is regarded by others as a decomposition product and not existing preformed. Besides other substances, Parsons has separated an acid, which he regards as similar to the sclerotic acid of Dragendorff, and a substance soluble in ether but not in alcohol.

Physiological Actions

Several important investigations of the actions of ustilago have been made in the laboratory of experimental therapeutics of Jefferson Medical College, which agree for the most part with the account to follow, and which we owe to Dr. Hoffman, whose work was done in the college laboratory three years ago.

The researches above referred to will appear in a special volume, now preparing.

Both in cold- and warm-blooded animals, ustilago acts as a spinal excitant, causing convulsions of a tonic character. It also heightens sensibility and the reflex function, so that the least irritation of the skin induces general tonic convulsions of the tetanic or strychnic character. Frequent irritation and repeated convulsions rapidly exhaust the animal. On the other hand, quiet, darkness, and relief from all irritation, diminish the severity of the convulsions, and prolong life, if not prevent a fatal result. Death may ensue in a convulsion by tetanus of the respiratory muscles. Muscular tremors, general, occur in warm-blooded animals, and muscular weakness (paresis) appears in the intervals between the convulsions. The irritability of the motor nerves, and, toward the end, of the sensory nerves also, declines, but is not entirely lost, and the contractility of the muscles lessens somewhat. That the convulsions are spinal, is a fact proved by destroying the cord in a frog before administering the medicament, when no muscular action of any kind takes place. Section of the medulla or decapitation does not prevent the occurrence of the convulsions.

Ustilago slows the heart, and by numerous control experiments this action was shown to be due to stimulation of the pneumogastric and its terminal ganglia. It dilates the pupil, and affects the acuteness of vision for near objects.

We have no exact data in regard to the action of this agent on the uterine system. An impregnated cat, dying by a merely lethal dose slowly, did not abort; but it is said that pregnant cows and bitches, after eating ustilago, have dropped their young.

The modes of dying are two: in the tetanus; by exhaustion. In the former, the respiration is arrested, violent tonic extension of the voluntary muscles takes place, the head being drawn back, the toes incurved. In the latter there is gradually increasing paresis between the convulsions, and slowing of the heart's action. The difference is largely due to the dose and rapidity of administration. A lethal dose for a rabbit weighing 25 ounces seems to be one drachm of the fluid extract.