A textbook of human physiology / translated from [the] 6th German edition by W. Stirling.

  • Landois, Leonard
Date:
1888
Catalogue details

Licence: Public Domain Mark

Credit: A textbook of human physiology / translated from [the] 6th German edition by W. Stirling. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

    87/980 page 35
    [Hammarsteu and EicliwaUl find that, although paraglobuliu and tibi iuogeii are soluble in solutions of common salt (containing 5 to 8 per cent, of the salt), a saliiie solution of 12 to 16 per cent, is required to precipitate the fibrinogen, leaving still in solution paraglobuliu, which is not precipitated until the amount of salt exceeds 20 per cent.] Properties of the Fibrin-Factors.—They are insokible in pure water, but dissolve in water containing O in solution. Both are soluble in very dilute alkalies, e.(j., caustic soda, and are precipitated from this solution by CO^. They are soluble in dilute common salt—like all globulins—but if a certain amount of common salt be added in excess, they are precipitated. Very dilute hydrochloric acid dissolves them, but after several hours they become changed into a body resembling syntouin or acid-albumin (§ 249, III.). Fibrinogen held in solution by common salt coagulates at 52° to 55° C. [Fred^ricq finds that fibrinogen exists as stick in the plasma ; it coagulates at 56° C, and the plasma thereafter is uncoagulable.] 4. Preparation of the Fibrin-Ferment—(o) Mix blood-serum (ox) with twenty times its volume of strong alcohol, and after one month filter off the deposit thereby produced. The deposit on the filter consists of coagulated insoluble albumin and the ferment; dry it carefully over sulphuric acid, and reduce to a powder. Triturate 1 gram of the powder with 65 c.c. of water for ten minutes, and filter. The ferment is dissolved by the water, and passes through the filter, while the coagulated albumin remains behind {Schmidt). {{h) Gamgee's Method.—Buchanan's '' washed blood-clot (p. 33) is digested in an 8 per cent, solution of comniou salt. The solution so obtained possesses in an intense degree the properties of Schmidt's fibrin-ferment.] In the preparation of fibrino-plastin, the ferment is carried down with it mechanically. The ferment seems to be formed first in fluids outside the body, very probably by the solution of the colourless corpuscles. JMore ferment is formed in the blood the longer the interval between its being shed and its coagulation. It is destroyed at 70° C. Blood flowing directly from an artery into alcohol contains no ferment It is also formed in other protoplasmic parts (Jlauschcnbach), e.g., in dead muscle, brain, suprarenal capsule, spermatozoa, testicle {Foa and Pcllacani), ami in vegetable micro-organisms {e.g., yeast] and piotozoa {Grohman/i), [so that it would seem to be a general product of protoplasm. As the ferment does not pre-exist in colourless blood-corpuscles, it seems to be formed from some mother-substance in them, the blood-plasma itself decomposing this substance]. Coagulation Experiments.—According to A. Schmidt, if pure solutions of (1) fibrinogen, (2) fibrino-plastin, and (3) fibrin-ferment be mixed, fibrin is formed. The process goes on best at the temperature of the body ; it is delayed at 0° ; and the ferment is destroyed at the boiling-point. The presence of O seems necessary for coagulation. The amount of the ferment appears to be immaterial; large quantities produce more rapid coagulation, but the amount of fibrin formed is not greater. [Foa and Pellacani find that a filtered watery extract of fresh brain, cajisule of the kidneys, testes, and some other tissues, when injected into the blood-vessels of a rabbit, causes coagulation of the blood in the pulmonary circulation and the heart, death being caused by the action of a substance identical with the fibrin-ferment.] The amount of salts present has a remarkable relation to coagulation. Solutions of the fibrin-factors deprived of salts, and redissolved in very dilute caustic soda, when mixed, do not coagulate until sufficient NaCl be added to make a 1 per cent, solution of this salt (Schmidt). [Green finds that calcium sulphate brings about coagulation in plasma which shows little or no tendency to clot, while coagulation in its absence is almost or quite prevented.] When blood or blood-plasma coagulates, all the fibrinogen is used up, so that the serum contains only fibrino-plastin and fibrin-ferment; hence, the addition of hydrocele fluid (which contains fibrinogen) to serum causes coagulation. [Hammarsten's Theory.—Hammarsten's researches led him to believe that fibrino-plastin is quite unnecessary for coagulation. According to him, fibrin is formed from one body, viz., fibrinogen, which is present in plasma when it is acted upou by the fibrin-ferment; the latter, however, has not been obtained in a pure
    digitised image 1
    digitised image 2
    digitised image 3