A radioassay for angiotensin converting enzyme

Kenneth W. Ryder, Hannis Thompson, Daniel Smith, Martha Sample, Richard B. Sample, Tjien O. Oei

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Current methods for measuring angiotensin converting enzyme activity (EC 3.4.15.1, ACE) are somewhat cumbersome and have limited the general availability of the test. We describe here a simple four-step radioassay for ACE which uses the substrate 14C-Hippurate-l-Histidyl-l-Leucine and measures the product, 14C-Hippurate. We found that incubation at pH 7.0 (Hepes buffer) increased the sensitivity of the test by 50 percent when compared to results obtained with the pH 8.0 buffer normally used for ACE assays. A split sample comparison study between the radioassay and the spectrophotometric method showed good correlation (n = 47; mean, spectrophotometric, 26.0 U/mL; mean, radioassay, 26.1 U/mL; m = 0.86; b = 3.9; r = 0.868). We found that there was no significant difference between the spectrophotometric, kinetic and radioassay (Newman-Keuls multiple range test), but the liquid chromatographic method gave results significantly different from the other methods. The assay for ACE described here combines enhanced technical ease with the sensitivity of a radioassay.

Original languageEnglish (US)
Pages (from-to)302-305
Number of pages4
JournalClinical Biochemistry
Volume17
Issue number5
DOIs
StatePublished - 1984

Fingerprint

Peptidyl-Dipeptidase A
Assays
Buffers
Enzyme activity
Leucine
Availability
Kinetics
Liquids
Substrates
hippuric acid

Keywords

  • angiotensin converting enzyme
  • enzyme tests
  • radioimmunoassay

ASJC Scopus subject areas

  • Clinical Biochemistry

Cite this

Ryder, K. W., Thompson, H., Smith, D., Sample, M., Sample, R. B., & Oei, T. O. (1984). A radioassay for angiotensin converting enzyme. Clinical Biochemistry, 17(5), 302-305. https://doi.org/10.1016/S0009-9120(84)90601-5

A radioassay for angiotensin converting enzyme. / Ryder, Kenneth W.; Thompson, Hannis; Smith, Daniel; Sample, Martha; Sample, Richard B.; Oei, Tjien O.

In: Clinical Biochemistry, Vol. 17, No. 5, 1984, p. 302-305.

Research output: Contribution to journalArticle

Ryder, KW, Thompson, H, Smith, D, Sample, M, Sample, RB & Oei, TO 1984, 'A radioassay for angiotensin converting enzyme', Clinical Biochemistry, vol. 17, no. 5, pp. 302-305. https://doi.org/10.1016/S0009-9120(84)90601-5
Ryder, Kenneth W. ; Thompson, Hannis ; Smith, Daniel ; Sample, Martha ; Sample, Richard B. ; Oei, Tjien O. / A radioassay for angiotensin converting enzyme. In: Clinical Biochemistry. 1984 ; Vol. 17, No. 5. pp. 302-305.
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