The activation and inhibition of 5-nucleotidase.
The activation and inhibition of 5-nucleotidase have not been much studied. According to previous papers by Reis (1937, 1950) magnesium activates this enzyme to a much smaller extent than it does the non-specific phosphomonoesterase 'alkaline phosphatase'. Kaye (1955) mentions that zinc inhibits 5-nucleotidase, but his evidence in scanty. We have limited our study to human tissues, and have used aorta wall as a source of 5-nucleotidase, where it is free from non-specific phosphatase activity, and placenta, which has both enzymes.