Figure 2.

Perilipin is expressed in β-cells and α-cells of rat islets of Langerhans. Fluorescence photomicrographs of double- and triple-immunostained rat islets. A, Staining for perilipin (red). B, Staining for insulin (green). C, Merged image of A and B, demonstrating that the majority of the islet β-cells harbor perilipin. Arrowheads exemplify colocalization (yellow) of perilipin and insulin. D, Staining for perilipin (red). E, Staining for somatostatin (green). F, Merged image of D and E demonstrating that islet δ-cells are devoid of perilipin. Staining for perilipin (G; red), glucagon (H; green), and PP (I; blue) is shown. J, Merged image of G–I demonstrating that perilipin is not present in PP cells but is expressed in a subpopulation of α-cells. Colocalization of perilipin and glucagon (yellow) is exemplified by arrowheads. Scale bar (A, valid for A–J), 50 μm. Details of staining procedure and antibodies used are given in Materials and Methods and Table 1, respectively.