Islet NOS activities, insulin secretion, and expression of GPR40 and iNOS after treatment with palmitate and GPR40 antisense.

<p>Isolated islets were pretreated for 24 h with either the M40 antisense morpholino or a non-specific random sequence morpholino (control). The islets were incubated for 30 min in absence or presence of palmitate and then cultured with palmitate±M40 for a further 24 h. (A) M40 caused a marked suppression of palmitate-induced iNOS and ncNOS activities as well as a reduced insulin release (black bars). The results from the control morpholino are indicated by white bars. Values are mean±s.e.m for 4 different experiments performed at different occasions. ** p<0.01; *** p<0.001. (B) Expression of GPR40 (green) and iNOS (red) in islets cultured with palmitate (A-C) or palmitate+M40 (D-F). A and D = GPR40; B and E = iNOS, C and F = overlay. Bar indicates 5 μm. (C) Immunostaining and confocal images of formaldehyde-fixed β-cells. The expression pattern of insulin (red), GPR40 (green) and iNOS (yellow) from dispersed β-cells cultured with palmitate is shown. A = insulin, B = GPR40, C = iNOS and D = overlay. E–H show absence of expression of GPR40 (F) and iNOS (G) after M40 treatment. E = insulin, H = overlay. Bar indicates 5 μm.