In order to obtain a highly concentrated, pure and super-hot [γ-32P] ATP, we improved the purification method of super-hot [γ-32P] ATP which was synthesized by the method of Johnson and Walseth (1979) . The super-hot [γ-32P] ATP was synthesized in a relatively large volume (2 ml) of reaction mixture and purified using semi-micro scale anion exchange chromatography (Dowex 1×2, 60-70μl column volume) . In combination with washing the reaction product with certain organic solvents, this chromatography technique makes it possible to obtain a highly concentrated and pure super-hot [γ-32P] ATP (approx.7000 Ci/mmol; 20-30 mCi/ml) from [32P] Pi of any commercial source in a good yield.
The effects of higher-energy photon from123I (p, 5n) on the SPECT image quality were evaluated. The quality was evaluated by image contrast and %rms. Image contrast had similar tendency to planar and SPECT FWHM value. %rms was affected by septal penetration. Using 140 keV high resolution collimator (140 keV HR), image contrast was superior to that for 300 keV medium energy collimator (300 keV ME), but septal penetration rate (SPR) was 18% and %rms was 10.5. When quantitation is required, the collimator with less SPR than 18% is recommended for SPECT imaging. Using 300 keV ME, SPR was 0.05%, but spatial resolution and image contrast were inferrior to that for 140 keV HR.
Plasma vasoactive intestinal peptide (VIP) concentrations of normal individuals and patients with pancreatitis were studied using a VIP RIA kit. The inter-assay and intra-assay variation of this kit were between 2.1 and 9.4%. The VIP levels increased in the acute phase of acute pancreatitis and patients with chronic pancreatitis. The VIP concentration increased during the first 30 min of glucose tolerance test, but this increase was much smaller than that in insulin. These results suggest that this kit is useful for physiologic and pathologic changes in the VIP level.