Metehan UZUN, Nesrin SULU

Oksitosin ve fizyolojik etkileri

Oksitosin (OT), hipotalamusta supraoptik ve paraventriküler çekirdeklerde sentezlenen dokuz amino asitten kurulu peptit yapılı bir hormondur. Hormonun doğumda ve sütün indirilmesi olaylarında rolü çok iyi bilinmektedir. Hipotalamusun dışında bir çok farklı merkezsel sinir sistemi bölgesinde ve omurilikte OT ve reseptörlerinin belirlenmesi, hormonun; zorlanım (stres), beslenme, cinsel ve annelik davranışları ile ilişkilendirilmesine neden olmuştur. Son yıllarda ayrıca, OT' in pankreas ve şeker metabolizması, üreme fizyolojisi, özellikle timüs fizyolojisi olmak üzere bağışık (immün) sistem, ve kalp damar sistemi üzerine olan etkileri de yoğun bir şekilde araştırma konusu olmuştur. Böylelikle hormon için yapılan klasik tanımlama değişerek OT organizmada çok farklı amaçlar doğrultusunda kullanılabilen bir molekül ve bir nörotransmitter olarak tanımlanmaya başlanmıştır.

Anahtar Kelimeler:

oksitosin, fizyoloji, genel bakış

Oxitocin and its physiological effects

Oxytocin (OT) is a peptide hormone made up of nine amino acids and produced in supraoptic and paraventricular nuclei. Its role in parturition and milk withdrawal is well known. Detection of OT and its receptor in various regions of the Central Nervous System and m. spinalis has led to find out its relationship with stress, nutrition, sexual and maternal behaviour. In recent years, its effect on immun system, reproductive physiology, cardivascular system, and particularly on pancreas and sugar metabolism and on physiology of thymus have intensively been investigated. Thus the classical meaning of the hormone has changed and nowadays it is being defined as a molecule and a neurotransmitter which has many function in the body.

Keywords:

oxytocin, physiology, reviews,

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1.Kelly J and Swanson LW: Additional forebrain regions projecting to the posterior pitiutary: Preoptic region, bed nucleus of the stria terminalis and zona incerta. Brain Res. 197:1-9,1980.
2.Zimmerman EA, Nilaver G, Hou-Yu A and Silverman AJ: Vasopressinergic and oxytocinergic pathways in the central nervous systems. Fed Pwc, 43: 91-96, 1984.
3.Knight TW: The effect of oxytocin and adrenaline on the semen output of ram. J Rep rod Fert, 39: 329-336, 1974.
4.Arletti R, Benelli A and Bertolini A: Influence of oxytocin on feeding behaviour in the rat. Peptides, 10:89-93, 1989.
5.Arletti R, Benelli A and Bertolini A: Influence of oxytocin on nociception and morphine antinociception. Neuropeptides, 24:125-129, 1993.
6.Arletti R, Calza L, Giardino L, Benelli A, Cavazzuti E and Bertolini A: Sexual impotance is associated with a reduced production of oxytocin and with a increased production of opioid peptides in the paraventricular nucleus of male rats. Neurosci Letter, 233:65-68, 1997.
7.Yu GZ, Kaba H, Okutani F, Takahashi S, Higuchi T and Seto K: The action of oxytocin originating in the hypothalamic paraventricular nucleus on mitral and granule cells in the rat main olfactory bulbs. Neuroscience, 72:4, 1073-1082, 1995.
8.Elands J, Resink A and De Kloet ER: Oxytocin reseptors in the rat thymic gland. Eur J Pharmacol, 151:345-352, 1988.
9.Stock S, Fastbom J, Björsktrand E, Ungerstedt U and Uvnas-Möberg K: Effects of oxytocin on in vivo release of insuline and glucagon studied by microdialysis in the rat pancreas and autoradiographic evidence for [3H] oxytocin binding sites within the islets of Langerhans. Regul Peptides, 30:1-13,1990.
10.Favaretto ALV, Ballejo GO, Albuqerque-Araujo WIC, Gutkowska J, Antunes-Rodrigues J and McCann SM: Oxytocin releases atrial natriuretic peptide from rat atria in vitro that exerts negative inothropic and chronotropic action. Peptides, 18:9, 1377-1381, 1997.
11.Dawood MY and Khan-Dawood FS: Oxytocin. In: Clinical Reproductive Endocrinology, ed. Sherman RF, Page: 233- 249, Churchill Livingstone, New York. 1985.
12.Al-Eknah MM and Homeidea AM: A review of some aspects of the pharmacology of oxytocin in domestic animals. Vet Res Comm, 15(1): 45-55, 1991.
13.Burbach JPH, Adan RAH and de Bree FM: Regulation of oxytocin gene expression and forms of oxytocin in the brain. Ann NY Acad Sci, 652:1-13, 1992.
14.Moore F: Evolutionary precedents for behavioral actions of oxytocin and vasopressin. An NY Acad Sci, 652:156-165, 1992.
15.Petty MA, Lang RE, Unger T and Ganten D: The cardiovascular effect of oxytocin in conscious male rats. Eur J Pharmacol, 112:203-210, 1985.
16.Rogers RC and Herman GO: Oxytocin, oxytocin antagonist, TRH- and hypothalamic paraventricular nucleus stimulation effects on gastric motility.Peptides, 8:505-513, 1987.
17.Olson BR, Drutarösky MD and Chow MS: Oxytocin and an oxytocin agonist administrated centrally decrease food intake in rats. Riptides, 12:113-118, 1991. 18.Herbert J: Oxytocin and sexual behaviour. British Medical j,309:891-892,1994.
19.Murphy MR, Seckl JR, Burton S, Checkley S A and Llghtman SL: Changes in oxytocin and vasopressin secretion during sexual activity in man. J Clin Endoc Me tab, 65:738-741, 1987.
20.Carter CS: Oxytocin and sexual behaviour. Neurosci and Biobehav Reviews, 16:131-144, 1992.
21.Forsling ML, Judah JM and Windle RJ: The effect of vasopressin and oxytocin on glomerular filtration rate in the conscious rat: contribution to the natriuretic response. J of Endocrinology. 141: 59-67, 1994.
22.Windle RJ and Forsling ML: The renal actions of oxytocin in the conscious rat. J ofPhysiol and Pharmacol, 42:417-426, 1991.
23.Windle RJ, Judah JM and Forsling ML: Do vasopressin and oxytocin have synergistic renal effects in the conscious rat? J of Endoc, HA: 441-448, 1995.
24.StoeckelME, Freund-Mercier MJ, Palacios JM, Richard PM and Porte A: Autoradiographic localizations of binding sites for oxytocin and vasopressin in the rat kidney. J of Endoc. 113: 179-182,1987.
25.Windle RJ, Judah JM and Forsling ML: Effect of oxytocin receptor antagonist on the renal action of oxytocin and vasopressin in the rat. J of Endoc, 152: 257-264, 1997.
26.Sjöguist M, Huang W, Jacobsson E, Lee L and Ulfendahl HR: Natriuretic role of oxytocin in sodium homeostasis in rats. Adv İn Exp Med And Bio. 395:353-354, 1995.
27.Windle RJ, and Forsling ML: Renal responses to oxytocin during the days of the oestrous cycle in the rat. J of Endoc, 154:347-353, 1997.
28.Tamarova ZA: Effect of vasopressin and oxytocin on spontaneous unit activity of dorsal horn cells in the isolated spinal cord of young rats. Neurophysiol, 17:221-226, 1985.
29.Altszuler N and Hamshire J: Oxytocin infusion increases plasma insuline and glucagon levels and glucose production and uptake in the normal dog. Diabetes, 30: 112-114, 1981.
30.KnudtzonJ: Acute effects of oxytocin and vasopressin on plasma levels of glucagon, insulin and glucose in rabbits. Horm Metabol Res 15:103-106, 1981.
31.Sulu N, Uzun M, Sel T and Çınar A: Effect of intravenous injection of oxytocin on plasma levels of insulin and glucose in dairy cows. Israel J of Veterinary Medicine, 54:4, 118-121, 1999.
32.Mineo H, Ito M, Muto H, Kamita H, Hyun S and Onaga T: Effects of oxytocin, arginine-vasopressin and lysine-vasopressin on insulin and glucagon secretion in sheep. Res in Veterinary Science, 62:105-110, 1997.
33.Wallin LA, Fawcet CP and Rosenfeld CR: Oxytocin stimulates glucagon and insulin secretion in fetal and neonatal sheep. Endoc, 125: 2289-2296, 1989.
34.Gao ZY and Henquin JC: Arginine Vasopressin and Oxytocin effects in mouse pancreatic p-cells. Diabetes, 42: 914-921,1993.
35.Stock S and Uvnas-Möberg K: Influence of oxytocin and vasopressin infusions on gastrin, insulin, glucagon and VIP levels in conscious dogs. Acta Physiol Scand, 124:Supl. 542, 1985.
36.Petty MA, Lang. RE, Unger T and Ganten. D: The cardiovascular effect of oxytocin in conscious male rats. Eur J Pharmacol, 112: 203-210, 1985.
37.Haanwinckel MA, Elias LK, Favaretto ALV, Gutkowska J, McCann SM and Antunes-Rodrigues J: Oxytocin mediates atrial natriuretic peptide release and natriuresis after volume expansion in the rat. Pwc Natl Acad Sci, 92:7902-7906,1995.
38.Geenen V, Legros JJ and Fran.chimont P: The neuroendocrine Thymus: Coexistence of oxytocin and neurophysin in the human thymus. Science, 232:508-511, 1986.
39.Dawood MY and Khan-Dawood FS: Oxytocin. In: Clinical Reproductive Endocrinology, ed. Sherman RF, Page: 233- 249, Churchill Livingstone, New York. 1985.
40.Stock S, FastbomJ, Björsktrand E, Ungerstedt U and Uvnas-Möberg K: Effects of oxytocin on in vivo release of insuline and glucagon studied by microdialysis in the rat pancreas and autoradiographic evidence for [3H] oxytocin binding sites within the islets of Langerhans. Regul Peptides, 30:1-13,1990.
41.Yang J: Intrathecal administration of oxytocin induces analgesia in low back pain involving the endogenous opiate peptide system. Spine, 8:867-871, 1994.
42.Uvnas-Möberg K, Bruzelius G, Alster P, Bileviciute I and Lundeberg T: Oxytocin increases and a spesific oxytocin antagonist decreases pain threshold in male rats. Acta Physiol Scand, 144:487-488, 1992.
43.Berndtson WE and Igboeli G: Spermatogenesis, sperm output and seminal quality of Holstein bulls electroejaculated after administration of oxytocin. 7 Reprod Fert, 82:467-475, 1988.
44.Nicholson HD, Guldenaar SEF, Boer GJ and Pickering BT: Testicular oxytocin: effects of intratesticular oxytocin in the vat J of Endoc, 130: 231-238,1991.
45.Greer ER, Caldweel JD, Jonhson MF, Parange AJ and Pederson CA: Variations in concentration of oxytocin and vasopressin in the paraventricular nucleus of the hypothalamus during the estrous cycle in rats. Life Sci, 38: 2311,1986.
46.Tan GJS, Tweedale R and Biggs JSG: Oxytocin may play a role in the control of human corpus luteum. 7 of Endoc, 95: 65-72, 1982.
47.Swaap DF: The hypothalamo-neurohypophysial systems and reproduction. Prog Brain Res, 38:225, 1972.
48.Schams D, Prokopp HS and Barth D: The effect of active and passive immunisation against oxytocin on ovarian cyclicity in ewes. Acta Endoc. (Copenhagen), 103:337-344, 1983.
49.Jenkin G: The interaction between oxytocin and prostaglandin F2a during luteal regression and early pregnancy in sheep. Reprod Fertil Dev, 4:321-328, 1992.
50.Sheldrick EL and Flint APF: Endocrine control of uterine oxytocine reseptör in the ewe. 7 of Endocrinol, 136:4932- 4944,1985.
51.Robinson G and Evans JJ: Oxytocin has a role in gonadothropin regulation in rats. 7 of Endoc, 125:425-432, 1990.
52.Evans JJ, Robinson G and Catt KJ: Gonadothropin- releasing activity of neurohypophysial hormones: I. Potential for modulation of pitiutary hormone secretion in rats. J of Endoc, 122:99-106, 1989.