title: Hyperprolactinemia has no effect on plasma ghrelin levels in patients with prolactinoma.
abstract: OBJECTIVE
  Accumulating evidence suggests that prolactin is a modulator of body weight and composition and that it regulates some transporters in adipose tissue. It was demonstrated that hyperprolactinemia is associated with weight gain and obesity. Ghrelin is a novel hormone secreted from many organs including the pituitary gland. Ghrelin acts by regulating energy homeostasis and stimulating appetite. The aim of this study is to investigate whether ghrelin has a role in the case of weight gain in patients with prolactinoma.
  
  
  METHODS
  Forty-four patients with prolactinoma, both newly diagnosed and undergoing cabergoline treatment, were included in this study. Age- and sex-matched healthy subjects were included in the control group. Serum fasting glucose, insulin, lipid profile, and ghrelin levels were measured. Homeostasis model assessment of insulin resistance (HOMA-IR) was also calculated. Body mass index (BMI) and total fat ratio (%) of all the participants were assessed by bioelectrical impedance analysis using TBF-310GS™ (Tanita Corporation, Tokyo, Japan).
  
  
  RESULTS
  Patients with prolactinoma demonstrated significantly higher serum levels of fasting insulin, triglyceride, and waist and hip circumference measurement. No significant difference was found between the fasting glucose, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and HOMA-IR levels. BMI was significantly higher in the patients with prolactinoma than that in the control group (p<0.05). Additionally, the total body fat percentage was higher in the patients with prolactinoma than that in the control group; however, the difference was not significant (p>0.05). Furthermore, there was no significant difference in terms of the ghrelin levels between these groups. There was a correlation with serum ghrelin and growth hormone levels (p<0.02, rho=0.489). However, no significant correlation was obtained between serum prolactin or ghrelin levels and body fat percentage.
  
  
  CONCLUSIONS
  According to the results of our study, ghrelin has no effect on weight gain in patients with prolactinoma. Further studies are needed to evaluate whether ghrelin affects the prevalence of obesity in patients with prolactinoma.
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Tuncay
authors.initials: T
authors.lastname: Delibaşı
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Müyesser Sayki
authors.initials: MS
authors.lastname: Arslan
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Erman
authors.initials: E
authors.lastname: Çakal
authors.affiliation: Department of Endocrinology and Metabolism, Ankara University Faculty of Medicine, Ankara, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Şahin
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Oya
authors.initials: O
authors.lastname: Topaloğlu
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Esra
authors.initials: E
authors.lastname: Tutal
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: İlknur Öztürk
authors.initials: İÖ
authors.lastname: Ünsal
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Başak
authors.initials: B
authors.lastname: Karbek
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Bekir
authors.initials: B
authors.lastname: Uçan
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Aşkın
authors.initials: A
authors.lastname: Güngüneş
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Melia
authors.initials: M
authors.lastname: Karaköse
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Çalışkan
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Taner
authors.initials: T
authors.lastname: Demirci
authors.affiliation: Department of Biochemistry, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Gülfer
authors.initials: G
authors.lastname: Tabur
authors.affiliation: Department of Endocrinology and Metabolism, Dışkapı Training and Research Hospital, Ankara, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Özbek
keywords: Hyperprolactinemia; ghrelin; weight gain