Morphology, localization, and patterns of ghrelin-producing cells in stomachs of a morbidly obese population.

BACKGROUND

The role of the hormone ghrelin in the pathogenesis of morbid obesity is unclear. Researchers have identified its involvement in multifunctional activities that include appetite regulation, intestinal motility, release of growth hormone, and cell proliferation. The purpose of this study is to investigate and distinguish a pattern, if present, in ghrelin-producing cells and to record their distribution and quantity in a heterogenic morbidly obese population.

SETTING

The Bariatric & Metabolic Institute, Section of Minimally Invasive Surgery, Cleveland Clinic Florida, Weston, FL.

MATERIALS AND METHODS

Thirty-six patients who underwent sleeve gastrectomy for morbid obesity were evaluated for number and distribution of gastric ghrelin. Sections of fundus, body, and antrum were evaluated by using a ghrelin antibody staining technique. The gross specimens were divided into the following 3 zones: (1) fundus; (2) body; and (3) antrum. Three sections were then submitted from each zone. The ghrelin cells were counted using an image analyzer (MetaMorph; Universal Imaging Corporation, Downingtown, PA) after staining the blocks with antighrelin antibody. Counting ghrelin cells was standardized, and for each section 10 high-power fields were examined at ×4000. Our statistical analysis entailed a Student t test to compare the number of cells by age, sex, race, diabetic/nondiabetic, and body mass index. A P-value <0.05 was considered statistically significant.

RESULTS

Thirty-six patients (female 20/male 16) were studied. The average age of these patients was 45.6 (18 to 71) years. Race distribution was as follows: whites, 50% (18); African American, 13.9% (5); and Hispanic, 36.1% (13). Patients with diabetes comprised 13.9% of the cohort (5). Average body mass index was 44.9 kg/m (31 to 70). Significant differences in ghrelin cell distribution were found when comparing gastric anatomy location. Ghrelin cells were significantly more abundant in the gastric fundus when compared with the body and the antrum. Quantities of cells in the antrum were significantly higher in the Hispanic population (P=0.0054). No significant differences among other groups were observed.

CONCLUSIONS

In conclusion, ghrelin-producing cells seem to be more abundant in the fundus of morbidly obese patients. No significant differences were found in terms of number of cells by age, sex, presence of diabetes, or body mass index. There was an incidental finding of a higher concentration of these cells located in the antrum of the Hispanic population when compared with the white cohort.