Enalapril is a dicarbocyl-containing peptide and angiotensin-converting enzyme (ACE) inhibitor with antihypertensive activity.

PDGF receptor kinase activity: PDGF receptor is immunoprecipitated from BALB/c 3T3 cell extracts with rabbit antiserum to the murine PDGF receptor for 2 hours on ice. Protein A-Sepharose beads are used to collect the antigen-antibody complexes. The immunoprecipitates are washed twice with TNET (50 mM Tris, pH 7.5, 140 mM NaCl, 5 mM EDTA, 1% Triton X-100), once with TNE (50 mM Tris, pH 7.5, 140 mM EDTA), and once with kinase buffer (20 mM Tris, pH 7.5,10 mM MgCl2). After stimulation with PDGF (50 ng/mL) for 10 minutes at 4 °C, different concentrations of drug are added to the reaction mixture. PDGF receptor kinase activity is determined by incubation with 10 μCi [7-33P]-ATP and l μM ATP for 10 minutes at 4 °C. Immune complexes are separated by SDS-PAGE on 7.5% gels.