The study of ghrelin and obestatin system in patients with essential hypertension

Abstract

Objective To measure the fasting plasma ghrelin and obestatin concentrations in essential hypertension(EH) patients with obesity,and to observe their relationship with blood pressure,obesity index, insulin resistance(IR),blood glucose and blood lipid. Methods 68 hypertensive obese patients,60 normotensive obese patients and 65 healthy controls were included in the study.The fasting plasma obestatin and ghrelin were measured using a radioimmunoassay method.The ghrelin/obestatin ratio was calculated. Results Hypertensive obese patients had lower plasma ghrelin and obestatin compared with normotensive obese patients(t= 3.771,P< 0.01;t= 4.373,P< 0.01）and controls(t= 16.451,P< 0.01;t= 17.862,P< 0.01）。Normotensive obese patients had lower plasma ghrelin and obestatin compared with controls(t= 13.121,P< 0.01;t= 13.686,P< 0.01）。Hypertensive obese patients had higher ghrelin/obestatin ratio than controls(t= 7.720,P< 0.01）。The ghrelin/obestatin ratio in normotensive obese patients was higher than controls(t= 4.587,P< 0.01）。In hypertensive obese group,the plasma ghrelin and obestatin were negatively associated with BMI(r=-0.882,P< 0.01;r=-0.806,P< 0.01），SBP(r=-0.787,P< 0.01;r=-0.837,P< 0.01），DBP(r= -0.769,P< 0.01;r=-0.810,P< 0.01），and the HOMA-IR(r=-0.800,P< 0.01;r=-0.810,P< 0.01）。In normotensive obese group,ghrelin and obestatin were all negatively associated with BMI(r=-0.577,P< 0.01;r=-0.372,P< 0.01） and HOMA-IR(r=-0.866,P< 0.01;r=-0.662,P< 0.01）。 The ghrelin/obestatin ratio was positively associated with BMI(r= 0.460,P< 0.01） and HOMA-IR(r= 0.420,P< 0.01）。 Conclusion The peripheral blood ghrelin,obestatin and ghrelin/obestatin ratio were significantly correlated with EH,obesity and IR.No correlation was observed between ghrelin/obestatin system and blood lipid or blood glucose. Key words: Hypertension; Obesity; Insulin resistance; Ghrelin; Obestatin