Experimental Studies on the Alteration of NPN (non-protein nitrogen) with Cold

Abstract

Experiments to determine the relationship between the exposure time following death from cold and the amount of residual NPN in blood and organs.
Sixty rabbits weighing about 2500 grams were used in these experiments. Their whole bodies except the head and face were immersed in water at a temperature of 2 to 10°C and fastened by tight binding. Their rectal temperatures were measured five minutes apart using a thermocouple thermometer. The measured amount of residual NPN in tissues and blood with each experiment group by the Kjeldahl method after the death are as follows:
1) The amount of residual NPN in organs and blood differed depnding on aggressiveness and the length of time until death.
2) When the length of time until death was relatively short, the amount of NPN in organs decreased and that in blood increased.
3) When the length of time until death was relatively long, the amount of NPN inorgans increased extremely and that in blood also increased.
4) The amount of residual NPN in organs and blood starts to change at the initial stage of aggression.