Porcine pancreas and parotid cell suspensions provide model systems in which to study the mechanism of induction of a specific protein, α-amylase, by hormones acting via cAMP. A highly purified antibody against porcine pancreatic α-amylase was prepared using affinity chromatography of the total IgG fraction derived from rabbit anti-α-amylase antiserum and was used to develop a radioimmunoassay for α-amylase. The antigen-antibody complex was separated from unbound α-amylase using either glutaraldehyde gelled α-amylase or a second antibody technique; a linear standard curve was achieved over a 100- to 1000-fold range of α-amylase concentration. Tissue homogenates did not interfere with this assay, and assayed levels of α-amylase in porcine pancreas were linear using 10-200 μg of homogenate. No levels or very low levels of α-amylase were detected in control tissues.