Toluene is an aromatic hydrocarbon has addictive and toxic effect that is used widely in the industry. Ghrelin was a recently identified multifunctional hormone that is found in many organs, including the liver. This study aimed to determine ghrelin expression via immunohistochemical methods in rats that were experimentally administered toluene, a toxic agent for liver.

For this purpose, 14 adult male Wistar-albino rats were divided into two equal groups. Animals in group I were used as control group. The rats in group II were exposed toluene (3000 ppm/1hour/day) for four-weeks. Rats from both groups were decapitated 30 days after the operation. The liver tissues were removed and fixed in % 10 neutral formalin solution. Then tissue specimens were embedded in paraffin and sectioned (thickness, 5 µm). The sections were immunohistochemically stained using avidin-biotin-peroxidase method for determination ghrelin immunoreactivity.

Ghrelin immunoreactivity in the hepatocytes was determined as strong (+3) in the control group and low (+1) or no staining in the toluene inhaled group. No immunoreactivity was observed in negative control specimens. Ghrelin immunoreactivity was detected in sections of rat stomach used as a positive control.

The results obtained in our study indicate that toluene inhalation causes a decrease in ghrelin expression in the liver.