11 Ibid., 1868.
The liver is doubtless the seat of blood-destruction, for the bile-pigments and leucocytes with red corpuscles in their interior have been found in its tissue. Nicolaides12 has shown that in the blood of the hepatic vein there may be a reduction of from one million to one million and a half of red corpuscles per c.m. In the embryo Neumann13 has shown that it may be the seat of the production of corpuscles, but there is no satisfactory evidence that in the adult this ever takes place.
12 Archives de Physiologie, 1882.
13 Archiv der Heilkunde, xv.
The remarkable rapidity with which, after a profuse bleeding, the normal proportion of red corpuscles is reached shows with what activity the development may proceed, and how favorable the conditions must be for their production. After the loss of a large quantity of blood the manufacture of new corpuscles may proceed at the rate of 30,000, 40,000, or even 50,000 a day.
What becomes of the red corpuscles? Here, again, is a question not satisfactorily settled. We do not know the average length of life of corpuscles. They are supposed to be short-lived—three weeks, according to Quincke. The need for their dissolution is assumed to provide pigment for the various secretions and tissues, and we occasionally see a few cells in the blood with a pallor which may be regarded as an indication of senility.
Positive evidence, however, of their destruction is afforded by the occurrence of the so-called corpuscles containing red corpuscles, which occur normally in red marrow and in the spleen, and under some circumstances in the lymphatic glands and liver. The red cells undergo gradual transformation into a yellow granular, and finally black, pigment. In normal spleen and marrow the numbers found are very variable; in fevers and cachectic states they may be in extraordinary numbers. Quincke and his pupil Peters14 have studied with great care this process of transformation of the red corpuscles and accumulation of the pigment in the cells of the marrow, spleen, liver, and lymph-glands, to which the term siderosis is applied. These pigment-granules are in the form of an iron albuminate, and are used in the development of new corpuscles. Thus, after repeated bleedings in animals, they may disappear completely in the restoration of the blood, while in animals into whose vessels blood has been transfused or injected subcutaneously the iron-containing cells in the various organs are very numerous, and even the cortical cells of the kidney contain numerous granules.
14 Deutsches Archiv f. klin. Med., Bds. xxv., xxvii., xxxii., xxxiii.
The amount of hæmoglobin in 100 grammes of healthy blood is 13.45 grm. (Preyer). Malassez estimated the quantity in a cubic millimeter of blood at between 0.125 and 0.134 milligramme, and, taking the corpuscular richness at from 4,000,000 to 4,600,000, he has estimated approximately the amount of hæmoglobin in each corpuscle.