Acid-base balance in cold-blooded vertebrates as a function of body temperature.
نویسندگان
چکیده
HOWELL, B. J., F. MT, BAUMGARDNER, K, BONDI, AND H. RAHN. Acid-base balance in cold-blooded vertebrates us a function of body temperuture. Am. J. Physiol. 218(Z) : 600-606. 1970.-Arterial blood pH values of unanesthetized frogs, toads, and turtles vary inversely with the temperature to which the animal has been acclimated. MeanA pH/A t for the three species is -0.016 between 5 and 37 C. PCO, increases and HCO, decreases as the temperature rises. The change in arterial pH is of the same magnitude as the change in the neutral point pH of water (pN) so the blood pH-pN is a constant value over the temperature range studied. The difference between the pH and pOH of the blood and thus the ratio OH-/H+ (antilog pH -pOH) must also be constant. This suggests that the acid-base status of cold-blooded vertebrates should be evaluated in terms of the constancy of the OH-/H+ ratio rather than blood pH. The apparent maintenance of this ratio as the animal’s body temperature changes may be of importance to the maintenance of osmotic pressure as well as to the protein buffering system of the blood.
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عنوان ژورنال:
- The American journal of physiology
دوره 218 2 شماره
صفحات -
تاریخ انتشار 1970