Alteration of plasma ghrelin levels associated with the blood pressure in pregnancy.

Ghrelin, an endogenous ligand for the growth hormone secretagogues, was originally isolated from rat stomach. It stimulates the release of growth hormone from primary pituitary cell cultures. We investigated the plasma concentration of ghrelin peptide in 16 nonpregnant women, 18 normal pregnant women, 20 patients with pregnancy-induced hypertension, and 10 postpartum women. The plasma concentration of ghrelin in nonpregnant women was 239.5+/-16.9 fmol/mL. The plasma concentration of ghrelin in normal pregnant women at the third trimester was 127.1+/-5.6 fmol/mL. There was negative correlation between plasma ghrelin concentration and systemic blood pressure in normal pregnant women (systolic: r=-0.564, P<0.05; diastolic: r=-0.610, P<0.01). Pregnant women with pregnancy-induced hypertension (177.9+/-14.6 fmol/mL, P<0.05) also had significantly higher levels of ghrelin compared with those of normal pregnant women. In addition, there was a significant correlation between plasma ghrelin levels and systemic blood pressure (systolic: r=-0.482, P<0.05; diastolic: r=-0.466, P<0.05). These results suggest for the first time that ghrelin might have some role in cardiovascular control during normal pregnancy and in pathophysiological conditions in pregnancy, such as pregnancy-induced hypertension.