The aim of the study was to clarify the role of the ob gene product – leptin in the initiation of liver regeneration in male and female rats of two stocks. We used adult male and female Wistar rats and Spontane ously Hypertensive Rats (SHR). Obese homozygous SHR subjects have a defective leptin receptor and moderat e changes in the leptin receptor are expected also in lean heterozygous SHR littermates. In our study we assessed the serum leptin concentration, alanine aminotransferase activity, liver DNA and triglyceride (TG) content in intact rats and in rats 48 hours after 67% partial hepatectomy (PH). Leptin concentrations increased in all rats after PH, while this increase was more expressed in female rats. We concurrently observed higher liver DNA and TG contents in female rats. Leptin causes TG cumulation in the regenerating liver. After PH liver preferentially utilizes fats. We conclude that a higher serum leptin concentration after PH in female rats had a beneficial effect on the initiation of liver regeneration. SHR heterozygous littermates tolerate PH worse.

        Key words: partial hepatectomy, leptin, spontaneously hypertensive rats, triglycerides.