Sıçan Nukleus Olivaris İnferiorundaki Toplam Nöron Sayısının Fiziksel Disektör Yaklaşımlarıyla Belirlenmesi

Year 2021, Volume: 8 Issue: 2, 12 - 17, 31.08.2021

Pınar Gürgör Bülent Ayas

Abstract

Amaç: Nukleus olivaris inferior, medulla oblongata ön yüzeyinde oliva denilen kabartıları oluşturan, beyin sapındaki en büyük ve karakteristik şekli olan bir çift nukleustur Sıçan Nukleus olivaris inferiorundaki (NOİ) toplam nöron sayısının, sayı hesaplamasında altın standart olarak kabul edilen fiziksel disektör olarak tanımlanan stereolojik yöntem ile belirlenmesi amaçlanmıştır.
Yöntemler: Eşit sayıda dişi ve erkek olmak üzere toplam 10 adet Wistar sıçan beyin saplarına, rutin parafin doku takibi uygulandı. Nöronlar, NOİ hacminin bilinen bir fraksiyonunda (kesit ve alan fraksiyonları) sistematik olarak örneklenmiş fiziksel ayırıcılarla sayıldı. Her bir NOİ'deki toplam nöron sayısı, sayılan nöronların kullanılan fraksiyonların tersi ile çarpılmasıyla hesaplandı. Verilerin analizinde Student’s t-testi kullanıldı. Grup varyanslarının homojenliği Levene’s test ile kontrol edildi. Hesaplamalarda ve yorumlamalarda istatistiksel anlamlılık düzeyi %5 olarak alındı.
Bulgular Dişi ve erkek sıçanların sağ NOİ'lerindeki toplam nöron sayısı sırasıyla 37014 ve 38707, sol NOİ'lerindeki toplam nöron sayısı 37014 ve 39614 olarak hesaplandı. Ne cinsiyetler arasında ne de sağ ve sol kısımlar arasında önemli bir farklılık gözlenmemiştir.
Sonuç: Bu sonuçlar, sol ve sağ nukleuslar arasında herhangi bir fark olmadığı konusunda daha önce yapılan çalışma sonuçlarını doğrulamaktadır. Ancak literatürde bildirilen 17000 ile 30000 arasında değişen rakamlarla çelişmektedir. Yazının sonunda bu parametre ile ilgili tutarsızlıklara yol açabilecek olası nedenler tartışıldı

Keywords

Nucleus olivarius inferior, cell count, stereology, physical disector

References

• 1. Taner D. Fonksiyonel Nöroanatomi. Üçüncü Baskı. ODTÜ Geliştirme Vakfı Yayıncılık ve İletişim AŞ-Metu Pres-Yayınları, Ankara. 2002.
• 2. Standring S. Gray’s Anatomy, The Anatomical Basis of Clinical Practice. 42nd Edition. Elsevier Churchill Livingstone, Edinburgh. 2020. 3. De Zeeuw CI, Holstege JC, Calkoen F, Ruigrok TJH, Voogd J. A new combination of WGA-HRP anterograde tracing and GABA immunocytochemistry applied to afferents of the cat inferior olive at the ultrastructural level. Exp Brain Res. 1988;447: 369–375.
• 4. Nauta WJH, Feirtag M. Fundemantal Neuroanatomy. New York. WH Freeman and Company. 1986; 280–288.
• 5. Voogd J, Feirabend HKP, Schoen SHR. Cerebellum and precerebellar nuclei, in “The Human Nervous System” (G. Paxinos ed.). San Diego, Academic Press. 1990;312–388.
• 6. Voogd J. The human cerebellum. J Chem Neuroanat. 2003;26: 243–252.
• 7. Gwyn DG, Nicholson JP, Flumerfelt BA. The inferior olivary nucleus of the rat: A light and electron microscopic study. J Comparative Neurology. 1977;174: 489–520.
• 8. Azizi AS, Woodward DJ. Inferior olivary nuclear complex of the rat: Morphology and comments on the principles of organization within the olivocerebellar system. J Comp. Neurol. 1987;263: 467–484.
• 9. Carpenter MB. Core Text of Neuroanatomy. 3rd Edition. Baltimore. Williams & Wilkins. 1985.
• 10. Martin JH. Neuroanatomy, Text and Atlas. Elsevier, Science Publishing Co Inc, New York. 1989.
• 11. Ruigrok TJH, Voogd J. Organization of projections from the inferior olive to the cerebellar nuclei in the rat. J Comp Neurol. 2000;426(2): 209–228.
• 12. Hall JE, Guyton AC, Tıbbi Fizyoloji. 13. Basım. Güneş Tıp Kitabevleri. 2017.
• 13. Bancroft JD and Stevens A. Theory and practice of histological techniques. 4th Edition, Churchill Livingstone. 1996.
• 14. Luna LG. Manual of histologic staining methods of the armed forces institute of pathology. New York, McGraw–Hill, Inc. 1968.
• 15. Gundersen HJG. Stereology of arbitrary particles. A review of unbiased number and size estimators and the presentation of some new ones, in memory of William R Thompson. Journal of Microscopy. 1986;143: 3-45.
• 16. Pakkenberg B, Gundersen HJG. The total number of neurons and glial cells in human brain nuclei estimated by the dissector and the fractionator. Journal of Microscopy. 1998;150: 1-20. 17. Korkmaz A, Çiftçi N, Boşnak M, Ağar E. A simplified application of systematic field sampling and low-cost video recording set up for viewing disector pairs - exemplified in the rat cochlear nucleus. Journal of Microscopy. 2000;200: 269-276.
• 18. Ayas B, Korkmaz A, Gürgör PN. Simultaneous Viewing of Disector Pairs with a Frame Grabber: A Practical and Economic Application of The Physical Disector on Systematically Sampled Section Fields. Cell & Tissue Biology Research, 9th National Histology and Embryology Congress with International Contribution; May 20-23; Adana-Turkey: 2008.
• 19. Pine SS, Landing BH, Shankle WR. Reduced inferior olivary neuron number in early down syndrome. Pediatric Pathology & Laboratory Medicine. 1997;17: 537–545.
• 20. Sjöbeck M, Dahlén S, Englund E. Neuronal loss in the brainstem and cerebellum–Part of the normal aging process? A morphometric study of the cerebelli and inferior olivary nucleus. Journal of Gerontology: Biological Sciences. 1999;54A(9): B363–B368.
• 21. Nishie M, Yoshida Y, Hirata Y, Matsunaga M. Generation of symptomatic palatal tremor is not correlated with inferior olivary hypertrophy. Brain. 2002;126: 1348–1357.
• 22. Nishie M, Mori F, Yoshimato M, Takahashi H, Wakabayashi K. A quantitative investigation of neuronal cytoplasmic and intranuclear inclusions in the pontine and inferior olivary nuclei in multiple system atrophy. Neuropathology and Applied Neurobiology. 2004;30: 546–554.
• 23. Tsuchiya K, Oda T, Yoshida M, Sasaki H, Haga C, Okino H, Tominaga I, Matsui K, Akiyama H, Hashizume Y. Degeneration of the inferior olive in spinocerebellar ataxia 6 may depend on disease duration: Report of two autopsy cases and statistical analysis of autopsy cases reported to date. Neuropathology. 2005;25: 125–135.
• 24. Bourrat F, Sotelo C. Postnatal development of the inferior olivary complex in the rat. III. A morphometric analysis of volumetric growth and neuronal cell number. Dev. Brain Res. 1984;16: 241–251.
• 25. Delhaye-Bouchaud N, Geoffroy B, Mariani J. Neuronal death and synapse elimination in the olivocerebellar system. I: Cell counts in the inferior olive of developing rats. J. Comp. Neurol. 1985;232: 299–308. 26. Napper RMA, West JR. Permanent neuronal cell loss in the inferior olive of adult rats exposed to alcohol during the brain growth spurt: a stereological investigation. Alcolism: Clinical and Experimental Research. 1995;19(5): 1321–1326.
• 27. Cunningham JJ, Sherrard RM, Bedi KS, Renshaw GM, Bower AJ. Changes in the numbers of neurons and astrocytes during the postnatal development of the rat inferior olive. J. Comp. Neurol. 1999;406: 375–383.
• 28. Maier SE, West JR. Alcohol and nutritional control treatments during neurogenesis in rat brain reduce total neuron number in locus coerulus, but not in cerebellum or inferior olive. Alcohol. 2003;30: 67–74.
• 29. Blatt GJ, Eisenman LM. A qualitative and quantitative light microscopic study of the inferior olivary complex of normal, reeler, and weaver mutant mice. The Journal of Comparative Neurology. 1985;232: 117–128.
• 30. Frederic F, Hainaut F, Thomasset M, Guenet JL, Delhaye-Bouchaud N, Mariani J. Cell counts of Purkinje and inferior olivary neurons in the ‘hyperspiny Purkinje cells’ mutant mouse. European Journal of Neuroscience. 1992;4: 127–135.
• 31. Herrup K, Shojaeian-Zanjani H, Panzini L, Sunter K, Mariani J. The numerical matching of source and target populations in the CNS: The inferior olive to Purkinje cell projection. Developmental Brain Research. 1996;96: 28-35.
• 32. Zanjani HS, Herrup K, Guastavino JM, Delhaye-Bouchaud N, Mariani J. Development studies of the inferior olivary nucleus in staggerer mutant mice. Developmental Brain Research. 1994; 82: 18–28.
• 33. Zanjani HS, Vogel MW, Delhaye-Bouchaud N, Martinou JC, Mariani J. Increased inferior olivary neuron and cerebellar granule cell numbers in transgenic mice overexpressing the human Bcl-2 gene. J. Neurobiology. 1997;32: 502–516.
• 34. Zanjani HS, Herrup K, Mariani J. Cell number in the inferior olive of nervous and leaner mutant mice. Journal of Neurogenetics. 2004;18: 327–339.
• 35. Korkmaz A, Çiftçi N. Neuron Counts in the Inferior Olivary Nucleus of Developing Rats: A Reevaluation of the Previously Reported Data by Means of Unbiased Stereology. International Summer School On Developmental Neuroscience. July 5–9; İzmir-Turkey: 1999.