Fig. 7. Detection of APSGFLGMRamide (CabTRP Ia) in the releasate from posterior midgut caecum (PMC) samples. (A) MALDI-FTMS spectrum of 0.5 µl of sample taken after a single PMC sample was immersed in high-K⁺ saline containing an inhibitor cocktail for 1 h at 4°C. (B) MALDI-FTMS spectrum of 0.5 µl of sample taken after a single PMC sample was immersed in physiological saline containing an inhibitor cocktail for 1 h at 4°C prior to tissue transfer to high-K⁺ saline. The arrow indicates the m/z position where CabTRP Ia would be found, if present in the sample. Spectra were measured using DHB as the matrix, and conditions were optimized for ions of m/z 1000, using the accumulation of 30 laser shots. Both A and B are shown at the same (m/z) scale.