A new spectrophotometric assay for 2′,3′-cyclic nucleotide 3′-phosphohydrolase activity in nervous tissue

✍ Scribed by Charles E. Dreiling; Cynthia Mattson

• Publisher: Elsevier Science
• Year: 1980
• Tongue: English
• Weight: 454 KB
• Volume: 102
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(80)90157-8

✦ Synopsis

A new continuous spectrophotometric method for determining 2',3'-cyclic nucleotide 3'-phosphohydrolase (EC 3.1.4.37) is described. The assay method involves monitoring the decrease in pH which accompanies the hydrolysis of 2',3'-cyclic AMP. The reaction is performed in the presence of phenol red and the pH change is followed spectrophotometrically by recording the decrease in absorbance of the basic chromophore at 560 nm. The assay method is sufficiently sensitive to make accurate determinations of CNPase activity in 20-~1 samples of CNS homogenates containing less than 5 pg protein. The primary advantage of the phenol red CNPase assay is the ease and speed with which it is performed.