Birkan YAKAN, Züleyha DOĞANYİĞİT, Tuba RIHTIM, Arzu YAY

DİŞİ SIÇAN MİDESİNDE GHRELİN EKSPRESYONU ÜZERİNE OVARİEKTOMİNİN ETKİLERİNİN ANALİZİ

Ghrelin, büyüme hormonu salgılanması, iştah, besin alımı, karbonhidrat metabolizması, gastrointestinal sitem, kardiovasküler sistem, hücre proliferasyonu ve üreme sistemi üzerine etkileri olan bir hormondur. Biz bu çalışmada bilateral ovariektominin mide dokusunda neden olduğu yapısal değişiklikleri, bu değişikliklerin sonucunda mide mukozasındaki ghrelin immünreaktivitesinin nasıl etkilendiğini belirlemeyi amaçladık.Bu çalışmada 36 adet dişi Wistar-albino sıçan kullanılmıştır. Bu sıçanlar, yedi eşit gruba ayrılmıştır. Daha sonra deney grupları östrojen uygulanan ve uygulanmayan gruplara ayrılmıştır. Deneyin sonunda sıçanların mide dokuları çıkarılmıştır. Dokulara rutin hematoksilen-eozin(HE) ve avidinbiyotin metodu ile ghrelin immünohistokimya boyama prosedürleri uygulanmıştır. Östrojen uygulanmayan ovariektomize sıçanlarda morfolojik farklılıklar gözlenmemiştir. Ovariektomiden sonraki 3. ve 5. gün gruplarının gastrik oksintik mukozalarında ghrelin pozitif hücrelerin sayısı önemli derecede artmıştır. Ovariektomiden sonraki 7.gün grubunda gastrik mukozada ghrelin pozitif hücrelerin sayısı azalmıştır. Bu azalma 17-? östrodiol uygulanmasından kaynaklanmış olabilir. Bu sonuçlar; bilateral ovariektomi gastrik mukozada histolojik değişikliklere neden olmazken, gastrik ghrelin immünreaktivitesi üzerine etkili olduğunu göstermektedir.

Analysis of Ovariectomy Effects on Ghrelin Expression in Female Rat Stomach

Ghrelin is a hormone, which has effects on growth hormone secretion, appetite, food intake, carbohydrate metabolism, gastrointestinal system, cardiovascular system, cell proliferation and reproductive system. In this study, we have intended to observe that bilateral ovariectomy will bring structural changes in the gastric tissue and as a result of these changes, affect how ghrelin immunoreactivity in the gastric mucosa.In study, 36 adult female Wistar-albino rats were used. These 36 rats were divided into seven groups. Later, experiment groups were divided into groups of estrogen-administrated and nonestrogen-administrated. At the end of the experiment, the rats' gastric tissues were removed. Tissues are administrated ghrelin immunohistochemical staining with avidin-biotin-peroxidase and routine Hematoxylin -Eosin (HE) method.In the groups of ovariectomized rats that are not administrated estrogen were not monitored with morphological differences. With the groups of the third and the fifth day after ovariectomy, the number of ghrelin positive cells in the gastric oxyntic mucosa significantly increased. With the group of the seventh day after ovariectomy, the number of ghrelin positive cells in the gastric mucosa was decreased. Decrease in ghrelin positive cells with ovariectomy may be caused by administration of 17 ? - estradiol.These results suggested that while bilateral ovariectomy causes no histological changes in the gastric mucosa, it is effective on gastric ghrelin immunreactivity.

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1. Kojima M, Hosoda H, Date Y, Nakazato M, Matsuo H, Kangawa K.Ghrelin is a growth hormone releasing acylated peptide from stomach. Nature 1999;402:656-660.
2. Tanaka M, Hayashida Y, Iguchi T, Nakao N, Nakai N, Nakashima K. Organization of the Mouse ghrelin gene and promoter: occurrence of a short noncoding firs exon. Endocrinology 2001; 142: 3697-3700.
3. Gnanapavan S, Kola B, Bustin SA, Morris DG, McGee P, Fairclough P, Bhattacharya S, Carpenter R, Grossman AB, Korbonits M. The tissue distribution of the mRNA of ghrelin and types of its receptor GHS-R in humans. Clin. Endocrinol Metab. 2002; 87: 2988-2991.
4. Kojima M, Hosoda H, Date Y, Nakazato M, Matsuo H, Kangawa K. Ghrelin: discovery of the natural endogenous ligand for the growth hormone secretagogue receptor. Trends. Endocrinol. Metab. 2001; 12: 118-122.
5. Papotti M, Ghe C, Cassoni P, et al. Growth hormone secrataguge binding sites in peripheral human tissues. J. Clin. Endocrinol. Metab. 2000; 85: 3803-3807.
6. Gualillo O, Caminos J, Blanco M, et al. Ghrelin, a novel placental-derived hormone. Endocrinology 2001;142:788-794.
7. Gaytan F, Barreiro ML, Caminos JE, Chopin LK, et al. Expression of Ghrelin and Its Functional Receptor, the Type 1a Growth Hormone Secretagogue Receptor, in Normal Human Testis and Testicular Tumors. The Journal of Clinical Endocrinology & Metabolism. 2004; 89: 400-409.
8. Gualillo O, Caminos J, Kojima M, et al. Gen-der and gonadal influences on ghrelin mRNA levels in rat stomach. Eur J Endocrinol 2001; 144: 687-690.
9. Caminos JE, Tena-Sempere M, Gaytan F, et al. Expression of ghrelin in the cyclic and pregnant rat ovary. Endocrinology 2003; 144: 1594-602.
10. Zigman JM & Elmquist JK. Mini review: from anorexia to obesity - the yin and yang of body weight control. Endocrinology 2003; 144: 3749-3756.
11. Kojima M, Kangawa K. Ghrelin: structere and function. Physiol Rev 2005: 85: 495-522.
12. Tena-Sempere M & Huhtaniemi I. Gonadotropins and gonadotropin receptors, Reproductive Medicine, Molecular, Cellular and Genetic Fundamentals, New York 2003, pp. 225-244.
13. Pagotto U, Gambineri A, Vicennati V, et al. Plasma ghrelin, obesity, and the polycystic ovary syndrome: correlation with insulin resistance and androgen levels. Journal of Clinical Endocrinology and Metabolism 2002; 87: 5625-5629.
14. Pagotto U, Gambineri A, Pelusi C, et al. Testosterone replacement therapy restores normal ghrelin in hypogonadal men. Journal of Clinical Endocrinology and Metabolism 2003;88: 4139-4143.
15. Saruhan B, Nergiz Y. The effects of administration estrogen and antiestrogen agents with ovaciectomized rats on uterin epithels.Journal of Dicle Medical. 2002; C: 1-2.
16. Tawadros N, Salamonsen L.A, Dimitriadis E, Chen C. Facilitation of decidualization by locally produced ghrelin in the human endometrium. Molecular Human Reproduction. 2007; 13: 483-489.
17. Budak E, Sanchez M, Bellver J,Simon C, et al. Interactions of the hormones leptin, ghrelin, adiponectin, resistin, and PYY3-36 with the reproductive system. Fertility and Sterility 2006; 85: 1563-81.
18. Levin F, Edholm T, Ehrström M, et al. Effect of peripherally administered ghrelin on gastric emptying and acid secretion in the rat. Regul Pept 2005; 131: 59-65.
19. Edholm T, Levin F, Hellström PM, Schmidt PT. Ghrelin stimulates motility in the small intestine of rats through intrinsic cholinergic neurons. Regul Pept 2004; 121: 25-30.
20. Date Y, Kojima M, Hosoda H. Ghrelin, a novel growth hormone-releasing acylated peptide, is synthesised is synthesized in a distinct endocrine cell type in gastrointestinal tract of rats and humans. Endocrinolgy 2000; 141, 4255-4261.
21. Ueno H, Yamaguchi H, Kangawa K, Nakazato M. Ghrelin: a gastric peptide that regulates food intake and energy homeostasis. Regul Pept 2005; 126: 11-19.
22. Druce M, Bloom S. Central regulators of food intake. Curr Opin Clin Nutr Metab Care 2003;6: 361-367.
23. Dzaja A, Dalal Mac, Himmerich H, Uhr M, Pollmacher T, Schuld A. Sleep enhances nocturnal plasma ghrelin levels in healthy subjects. Am J Physiol Endocrinol Metab 2004; 286: 963-967.
24. Nagaya N, Kangawa K. Ghrelin, a novel growth hormonereleasing peptide, in the treatment of chronic heart failure. Regul Pept. 2003; 114: 71-77.
25. Soriano-Guillen L, Barrios V, Campos-Barros A, Argente J. Ghrelin levels in obesity and anorexia nervosa: effect of weight reduction or recuperation. J Pediatr. 2004;144: 36-42.
26. Cummings E, Purnell JQ, Frayo SR. A preprandial rise in plasma ghrelin levels suggests a role in meal initiation in humans. Diabetes 2001; 50: 1714-1719.
27. Rindi G, Necchi V, Savio A, et al. Characterisation of gastric ghrelin cells in man and other mammals: studies in adult and fetal tissues. Histochem. Cell Biol. 2002;117:511-519.
28. Hosoda H, Kojima M, Matsuo H, Kangawa K: Purification and characterization of rat des-Gln14-ghrelin, a second endogenous ligand for the growth hormone secretagogue receptor. J Biol Chem, 2000; 29: 1995- 2000.
29. Guyton AC, Hall JE. Tıbbi Fizyoloji. Çavuşoğlu H (Çeviri Editörü). 9. Baskı, İstanbul, Nobel Tıp Kitapevleri, 1996: 315- 319. 30. Capella C, Vassallo G, Solcia E. Light and electron microscopic identification of the histamine-storing argyrophil (ECL) cell in murine stomach and of its equivalent in other mammals. Cell and Tissue Research 1991; 118: 68-84.
31. Bordi C, Dadda T, Azzoni C, Ferraro G. Classification of gastric endocrine cells at the light and electron microscopical levels. Microsc. Res. Techn.2000; 48: 258-271.
32. Davis JC. The relation between the pancreatic alpha cells and certain cells in the gastric mucosa. J Pathol Bacteriol. 1954 67 (1), 237- 240.
33. Lu D, Willard D, Patel IR. Aou protein is an antagonist of the melanocyte- stimulatinghormone receptor. Nature, 1994; 371: 799-802.
34. Sakata I, Tanaka T, Matsubara M, et al. Postnatal changes in ghrelin mRNA expression and in ghrelin-producing cells in the rat stomach. J Endocrinol 2002; 174: 463-471.
35. Sakata I, Nakamura K, Mamazaki M, et al. Ghrelin-producing cell exist as two types of cells, closed-and opened type cells, in the rat gastrointestinal tract. Peptides 2002; 23: 531- 536.
36. Narin N, Çetin E. Effect of ghrelin administration on some hematological parameters in rats.Journal of Health Sciences 2010; 19(3) :202-208.
37. Matsubara M, Sakata I, Reiko W, Yamazaki M, Inoue K and Sakai T. Estrogen modulates ghrelin expression in the female rat stomach. Peptides 2004; 25:289-297.