REPORT ON THE RECENT PROGRESS OF CHEMICAL AND MICROSCOPICAL PHYSIOLOGY AND PATHOLOGY

GeorgeE. Day
1845 The Lancet  
Medicine. Tais Reporf is founded on the Allthropochemie' of Simon, the 'Lehrbuch der Physiologischen Chemie' of Marchand, the' Lebrbuch der Physiologischen Chemie' of Lehmann, the German editions of .Mulder's 'Physiological Chemistry,' and the various periodicals devoted to chemico-microscopic investigations. I have purposely had recourse to those works which are least easy of access to the general reader, and this must be my apology for the very brief notice that I have taken of the late
more » ... ches of British chemists. That our own countrymen have not been altogether inactive in this most interesting, and hitherto almost untrodden field of sèientic research, and that their labours have been duly appreciated, is evinced by the circumstance that within the last few months German editions have appeared of Ancell's 'Lectures on the Blood,' Ancell's ' Lectures on the Theories of Liebig,' Golding Bird's 'Urinary Deposits,' Percy's' Observations on Diabetes,' and Wright on the Saliva.' Several of these translations are accompanied with valuable notes. THE BLooD. Distinctive characters of arterial and venous blood. Simon has published analyses of the blood from the carotid artery and jugular vein of horses: Analyses (1) and (2) in Table I , were made with the blood of a horse which took its ordinary food up to the time of its death; Analyses (7) and (8) with the blood of an old and emaciated horse. They show that arterial blood contains less solid residue, less fat, less albumen, less hsematin, less extractive matter and salts than venous blood ; the blood-corpuscles of arterial blood contain less colouring matter than those of venous blood. If we regard these analyses in connexion with those of Denis, Hering, Lecanu, Schultz, Antenrieth, Prevost andDumas,Sigwart, and Lassaigne, we are led to the conclusion that there are certain differences between the arterial and venous blood of the same animal, that these differences, however, are not constant, but vary in accordance with the health of the individual, the nature of the food, &c. Physiological reasoning would lead to a similar result. Blood of vena portal contrasted with arterial blood. The blood of the vena portae is darker than ordinary venous blood ; it coagulates slowly, and the clot assumes a gelatinous appearance and readily breaks. Simon analysed this blood in the two horses previously alluded to; the results are given in (3) and (9) Table I. If we contrast these with (1) and (7) , the arterial blood of the same animals, we shall find that there are only four points that yield coincident results. In the blood of the vena portae there is less fibrin, more fat, more extractive matters and salts, and the ratio of the colouring matter to the globulin is greater, than in arterial blood. Analysis (4) was made on another occasion for the express purpose of ascertaining the ratio of the haemaphasin to the haematín. The variations that occur in this blood in different animals, and at different times, are readily accounted for by the peculiar facility for absorption possessed by the branches of this vein, in consequence of their distributions over the chylopoietic viscera. The deficiency of fibrin may be explained in the following manner. In the first place, a large quantity of fluid may be absorbed by the vein, containing little or no fibrin, in consequence of which the relative proportion of fibrin in a given quantity of blood must be diminished, and secondly, it may arise from the torpidity of this portion of the circulation, and deficient action of oxygen. In consequence, of this latter reason, the metamorphosis of the blood-corpuscles mustbe deficient and retarded, and the solution of the developed corpuscles will not be duly effected. This accounts not only for the diminution of fibrin, but for the accumulation of the mature corpuscles, and for the consequent excess of haemaphaein to which the dark tint of this serum is attributable. A microscopic examination reveals a large number of fat vesicles Blood of hepatic vein contrasted with blood of portal vein. If we contrast analyses (10) and (6) with (9) and (5) respectively, we find that the blood of the hepatic vein is richer in solid residue, but poorer in fibrin, fat, globulin, and colouring matter than the blood of the portal vein ; the ratio of the colouring matter to the globulin, and the quantity of albumen is larger in the former than in the latter blood. These differences seem to indicate that the blood-corpuscles.( or at least the globulin, their principal oonsti. tuent,) take a greater share in the formation of bile, than the albumen, the chief constituent of the plasma. On diluting the blood of the hepatic vein with a solution of muriate of ammonia, and examining it under the microscope, the averaged-sized corpuscles were observed to be surrounded by a fillet of pearly excrescences ; a great excess of minute corpuscles of about one fourth or one sixth the usual size were likewise seen, which could only be recognized as blood-corpuscles by their yellow colour and their discoid form. The motions of these minute corpuscles resemble those of l3rown's molecules, and were much more active than those of the ordinary corpuscles in common blood. -Blood of renal vein contrasted with that of aorta. Simon was unable to obtain any fibrin from the small quantity of blood that he obtained from the renal vein, and circumstances prevented him from determining the globulin ; analyses (11) and (12) are therefore comparatively imperfect. With the microscope he found that in the unmixed blood of the renal vein the corpuscles united themselves into islets and amorphous groups in which the individual corpuscles could not be traced. On the addition of a solution of common salt, a large number of small and middle-sized corpuscles came in view, but not so many as in the blood of the hepatic vein, (vide supra.) TABLE I. Absolute composition of healthy venous blood in man. Simon has communicated two analyses (1) and (2) of Table II, in connexion with this subject, and analysis (4) made by Nasse, approximates closely to them. The blood in (1) was taken from a youth aged 17 years, in (2) from a girl aged 28. Simon sums up the general characters of blood in the following terms. It contains about 20g of solid constituents ; nor much more than 0'28 of fibrin, and about an equal amount of fat ; the blood-corpuscles considerably exceed the albumen in quantity, and contain about 5 or 68 of colouring matter. The salts of the blood have been analysed by Denis, (in all his analyses,) by Marchand, by Nasse, (4 a 3,) table II, and finally by Enderlin, who shows most distinctly that the ash yielded by the incineration of the solid residue of the blood contains neither carbonates nor free alkalies, but a considerable amount of tribasic phosphate of soda, to which the alkalinity of the blood is due. He accounts for the error in which previous chemists had fallen, by observing that the tribasic phosphate of soda 3 Na;0,POg, if exposed to a moist atmosphere containing carbonic acid, becomes converted into bibasic phosphate of soda and carbonate of soda, 2 NaO, HO, POg and Na 0, C02. Assuming the correctness of Enderlin's experiments, the lactates must be excluded from the list of the constituents of the blood.
doi:10.1016/s0140-6736(02)70970-7 fatcat:57wwlsz33fcrxpzwdg6jjriw74