R. R. Overman

Hemoglobin Types of Macaca irus and Macaca mulatta Monkeys

Hemoglobin of 30 Macaca mulatta monkeys and of 15 Macaca irus monkeys consisted of one electrophoretic component similar to human hemoglobin A. Twenty-one M. irus monkeys had two types of hemoglobin. In 20 animals the hemoglobin resembled human hemoglobin AJ, and in one animal it resembled human hemoglobin AI.

The Disappearance of K42 from the Nonuniformly Mixed Circulation Pool in Dogs

The disappearance of injected labeled substances which disappear rapidly from the circulation is discussed theoretically and tested in experiments with injected K42 in the dog. Comparing the inflow and outflow from a capillary bed, using semilogarithmic plots of label concentrations, events upstream are repeated downstream but displaced in time by the amount of the mean circulation time between the points of observation. Downward displacement occurs owing to the intervening loss of material, and smearing of the time relations is produced by the dispersing action of variable path lengths in the capillary labyrinth. For the circulation as a whole, the time relations consist of the sum of a periodic component and an aperiodic component. The periodic component is governed by the mixing relations in a virtual circulation whose architecture approximates that of the real circulation. Extrapolating the aperiodic component to zero time yields the volume of dilution of the injected material in the virtual circulation, providing that injection and sampling points are close together. When the points are separated, correction must be made for time delay and loss of label between. The initial slope is governed not only by the mean rate of exchange of injected substance with the tissues but also by the mean circulation time.

Comparison of the Intravascular Mixing and Disappearance of Radiosodium, Radiopotassiuin and T-1824

A method is presented utilizing the rapid intravenous injection of a dye-isotope mixture and rapid, serial arterial sampling which permits the determination of rates of disappearance of these materials from the vascular system. Since K+ traverses capillary endothelial walls at about twice the rate of Na+ it appears that these two ions, while being about the same size and having the same charge, are handled in different manners by the capillaries. Other variables obtainable from the T-1824 isotope time-concentration curves such as plasma volume, circulation time, cardiac output and isotope distribution volumes are also presented.

Transcapillary exchange rates in acute and intermittent hyperthermia.

The effects of severe, acute and mild, intermittent hyperthermia on the transcapillary exchange rates of Na24 and of K42 have been studied in dogs. Measurements were made before and after a single exposure to a rectal temperature of 42.5℃ for 1 hour, before and after a single exposure to a rectal temperature of 41.5℃ and before and after exposure to the seventh daily rectal temperature elevation to 41.5℃. The sodium exchange rate was seen to be altered in every instance in which a post-hyperthermic measurement was obtained. A measured change in the potassium exchange rate was found to exist only in the animals which had been exposed to daily bouts of intermittent hyperthermia for 7 days. Submitted on February 10, 1959