Physiological chemistry; a text-book and manual for students

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1916 Excerpt: ...thus still in many points obscure, we may consider their relation to clotting. It may be said, in passing, that the interpretation of the clotting of the blood really rests on the determination of the origin and significance of the plates. If any foreign substance wet by the blood is put into the blood stream, such as a needle or a thread put through a vein or artery, it is found that the foreign substance becomes covered with a deposit of' plates and that this deposit becomes covered by, or is partially converted into, fibrin. Moreover, when platelets are added to plasma and the latter clots, it will be observed that the platelets are the centers from which the fibrin formation starts. The relation of the plates to clotting was also shown by Wooldridge as follows: Dog's blood, which is incoagulable from the injection of peptone, becomes coagulable if a stream of C02 passes through it. The same is true of the peptone plasma, provided the dose of peptone has not been too large. Peptone plasma will clot spontaneously if C02 is passed through it, or if acetic acid is added to the plasma, or if the plasma be diluted with two or three volumes of water, but it will not clot spontaneously if diluted with two or three volumes of 1 per cent. NaCl. Wooldridge found that if such coagulable plasma was cooled to a low temperature and the platelet stuff centrifugalized out of the blood and the plasma then filtered through several thicknesses of filter paper so that the plasma was perfectly clear and free from plates (A-fibrinogen, as he called it), the plasma had lost its power of clotting when diluted with water or when C02 was passed through it, but it reobtained its power if the platelets either suspended in a little plasma or redissolved in very dilute alkaline salt ...