The problem of tissue sampling from experimental animals with respect to freezing technique, anoxia, stress and narcosis: A new method for sampling rat liver tissue …
RP Faupel, HJ Seitz, W Tarnowski, V Thiemann… - Archives of Biochemistry …, 1972 - Elsevier
RP Faupel, HJ Seitz, W Tarnowski, V Thiemann, CH Weiss
Archives of Biochemistry and Biophysics, 1972•ElsevierThe problems of the measurement of physiological concentrations of glycolytic intermediates
and related compounds in rat liver were investigated. Five hundred milligrams, tissue
samples, immersed in liquid nitrogen, remained at a temperature of more than 30° for about
15 sec. Not till then temperature dropped rapidly. When samples up to 24 g were cooled
only a disproportionately small prolongation of the initial phase was observed. The
dependency of freezing time on tissue weight was investigated for liquid nitrogen, CClF 3 …
and related compounds in rat liver were investigated. Five hundred milligrams, tissue
samples, immersed in liquid nitrogen, remained at a temperature of more than 30° for about
15 sec. Not till then temperature dropped rapidly. When samples up to 24 g were cooled
only a disproportionately small prolongation of the initial phase was observed. The
dependency of freezing time on tissue weight was investigated for liquid nitrogen, CClF 3 …
Abstract
The problems of the measurement of physiological concentrations of glycolytic intermediates and related compounds in rat liver were investigated. Five hundred milligrams, tissue samples, immersed in liquid nitrogen, remained at a temperature of more than 30 ° for about 15 sec. Not till then temperature dropped rapidly. When samples up to 24 g were cooled only a disproportionately small prolongation of the initial phase was observed.
The dependency of freezing time on tissue weight was investigated for liquid nitrogen, CClF3 and isopentane. Using the latter two the freezing time could be shortened significantly. Yet, even for isopentane, it remained still longer than 12 sec for a 500 mg tissue sample. A mathematical approach proved that—even under ideal conditions—500 mg of tissue immersed should need about 7 sec to freeze through.
A new method of liver sampling from unanaesthetized rats was developed and the physiological substrate concentrations were determined. AMP values were found to be as low as 15 nmoles/g liver. The time course of the alterations of substrate concentrations during anoxia was investigated and found to be nearly linear during the first 13.6 sec. Nembutal was shown to influence substrate concentrations severely, independent on narcosis-induced anoxia. AMP was found to be a highly sensitive parameter to stress.
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