Blood ghrelin, resistin, and adiponectin concentrations during the normal menstrual cycle

Abstract

To investigate changes of ghrelin, resistin, and adiponectin levels in the circulation during the normal menstrual cycle. Longitudinal study. The study was conducted at a university hospital. Eight healthy normally cycling women. The women were observed during a whole menstrual cycle. Daily blood samples were taken every morning, after overnight fasting, from day 2 of the cycle until the next menstrual period. Plasma acylated and unacylated ghrelin and serum resistin, adiponectin, FSH, LH, E(2), and P levels were measured in all blood samples. In all women serum FSH, LH, E(2), and P levels, normalized to the midcycle peak LH value, showed the typical changes of the normal menstrual cycle. Acylated and unacylated ghrelin, resistin, and adiponectin levels did not change significantly during the whole menstrual cycle. The present study shows for the first time that plasma ghrelin and serum resistin levels do not change significantly during the normal menstrual cycle. It is also confirmed that serum adiponectin levels remain stable throughout the cycle. It is suggested that ovarian steroid dynamics during the cycle have no effect on the secretion of these substances.