Physiological chemistry

1889 Journal of the Chemical Society Abstracts  
P h y s i o l o g i c a 1 C h e m i s t r y . Reduction of Oxyhaemoglobin in the Heart. By S. HANDLER (Zeit. Biol., 26,.--The analysis of the gases of tihe blood entering and leaving such a small organ as the heart of the frog or tortoise being out of the question, the spectroscopic method was employed. An ingenious apparatus, described and figured, was used ; a solution consisting of either rabbits' or calves' blood, with 9 parts of saline solution, was kept in the heart : in some cases tlhe
more » ... n some cases tlhe organ beat spontaneously ; in others only in response to stimulation ; the heart was placed in connection with a two-way cannula, and the whole suspended in a chamber connected with a mercurial reservoir, by raising or lowering which, fluid could be d r a w n into or drawn out of the heart, and then immediately subjected to spectroscopic examination in a part of the apparatus that was transparent. If the oxyliaemoglobin were not fully reduced, the solution was reCumed to the heart, examined again at intervals, and a note made of the time taken for the reduction to occur. The so-called auto-reduction that occurs in shed blood may be postponed indefinitely by a temperature of O", or by protection from atmospheric microbes. The authoress confirms Yeo's observation, that it is a ferment process. The other observations she makes are also very largely confirmatory of Yeo's work (J. PhysioZ., 6, 93) . The turtle's heart reduces oxy-hemoglobin much more quickly than the frog's heart (5-15 : 15-80 minutes). With regard to the influence of temperature on the rate of reduction, contradictory results were obtained. The most marked fact, however, was that an increase i n the rate of the heart's beat, and of the rate of reduction always go together ; but the latter is independent o€ the work done by t h e hear& as tested by filling the reservoir with different liquids-mercury, oil, blood, &c. Kroneoker obtained much the same result with skeletal muscles ; he found that fatigue depends on the frequency of contraction more than on the actual amount of wonk done. W. D. H. The Digestibility of Boiled Milk. By R. W. RAUDNITZ (Zeit. physiol. Chern., 14, 1-14) .-The di-fference of digestibility between boiled and fresh milk is a matter of great importance with regard to the feeding of infants. The present experiments were carried out on a dog, and are merely preliminary to others to be undertaken on a more extended scale. The animal was fed for the period of a, few days on unboiled milk, and then for another period on an equal quantity of the same milk (boiled). The amounts of lime, nitrogen, and fat were estimated both in the milk and in the excreta (urine and faxes), The animal w a~ also weighed daily; a second series of experiments was similarly conducted, but the results appear to be of less value, as by that time the dog seemed to have ceased growing, and had attained its adult state.
doi:10.1039/ca8895601225 fatcat:hvbgsxjhobcenkebr62a7gy5aa