Abstract

Nitric oxide (NO) is synthesised by different nitric oxide synthases (NOS) from Larginine and acts as a signal transducer in a variety of cells. The neuronal isoenzyme of NOS (nNOS) was recently found in rodent βcells and βcell lines. We provide evidence that nNOS is also present in the human βcell line CM and that the specific inhibitor of nNOS PIN is expressed in CM and INS-1 cells. Furthermore, we investigated the influence of glucose on the activity of nNOS and the expression of PIN and are able to show that both are increased by glucose stimulation in the βcell lines but not in the mouse fibroblastic cell line LTK. This indicates that nNOS and PIN play a role in the specific function of βcells, not only in rodents but also in humans.