STUDY ON INFLUENCE OF INACTIVATION ENZYME TECHNIQUES AND EXTRACTION PROCEDURES ON CEREBRAL PHOSPHORYLATED METABOLITE LEVELS BY P-31-NMR SPECTROSCOPY

Several enzyme inactivation and sacrifice techniques, such as freezing of severed head, microwave (MW) irradn., and brain freezing in situ have been compared by 31P NMR spectroscopy. In the brain exts. of decapitated and Mw-irradiated rats, the phosphocreatine (PCr), ATP, ADP, inorg. phosphate (I), and sugar phosphate (SP) levels show variations due to anoxic changes. Furthermore, Mw-irradiated rat brains show artifacts probably depending on the inactivation and activation of different enzymes by heating. Also PCr and Pi level changes between halothane N2O/O2 and thiopental anesthesia have been obsd. Moreover, a phosphodiester level increase has been obsd. in brain exts. of decapitated and Mw-irradiated rats. 31P NMR spectra of perchloric acid brain exts., compared to CH3OH-CHCl3-H2O exts., show changes in PCr, ATP and SP levels and furthermore, addnl. signals relevant to products of acid hydrolysis have been obsd.