# Gnaiger 1980 Thermal Analysis, Birkhaeuser

Gnaiger E (1980) Direct and indirect calorimetry in the study of animal anoxibiosis. A review and the concept of ATP-turnover. Thermal Analysis, Proc 6th Internat Conference Thermal Analysis, Birkhäuser:547-52. |

Gnaiger Erich (1980) Thermal Anylysis, Birkhäuser

*Abstract*: Direct microcalorimetric measurements of anoxic heat production in animals tend to be higher than expected from calculations based on biochemical and thermodynamic data (indirect calorimetry). Bioenergetic and thermodynamic analysis of known biochemical pathways revealed that 1) the proportionality factor relating the ratio of ATP-turnover to the rate of heat production in dissipative metabolism, *C*^{d}_{∞ATP} is not a constant; under anoxia this caloric equivalent of dissipative ATP-turnover is up to two times less than under aerobic conditions. 2) The varability of *C*^{d}_{∞ATP} is due to the entropy of reaction (compensation heat), *T*·Δ*S*_{r} which compensates for up to 50 % of the anoxic dissipative heat *T*·Δ_{i}*S*. Hence the rate of internal entropy production (the dissipation function), *T*·d_{i}*S*·d*t*^{-1} is not equivalent to the anoxic rate of metabolic heat production. This approximation holds true for aerobic conditions only.

* • Bioblast editor:* Gnaiger E

*AT Innsbruck Oroboros*

**•**O2k-Network Lab:

*Labels:* **MiParea:** Respiration

**Stress:**Hypoxia
**Organism:** Fishes, Annelids, Molluscs

**Preparation:** Intact organism

Microcalorimetry