Ghrelin expression in dissociated cultures of the rat neocortex

Ghrelin is a hormone, initially described as a gastric peptide stimulating appetite and growth hormone secretion, which also has an important role in the regulation of many other processes including higher brain functions. Ghrelin has been described in situ in different part of the brain, but so far there are no data about it in cell cultures. Therefore, we aimed this study to investigate the developmental pattern of ghrelin in dissociated cortical neuronal cultures. We applied the ABC immunocytochemical method for detection of ghrelin in dissociated cortical neurons from newborn rats, incubated for one day-, one week-, or two week old cultures. Our results clearly show that at the early stages of development of the network, majority of the neurons are ghrelin-positive, and their number decreases during the culturing period. As ghrelin is omnipresent in the early stages, when the neuronal differentiation and network formation take place, it may also influence the early development of synaptic formation and cell-to-cell interactions, both very important for the network functions like learning and memory.