Adebisi Sunday SAMUEL, Badamasi Ibrahim MOHAMMED

10-32 ppm Karbon Monoksiti Sağlayan Sigara Dumanının Wistar Ratlarının Referans Hafızalarına ve Hipokampüs Piramidal Hücre Sayılarına Etkisi

AMAÇ: Hafıza ile ilgili birçok çalışma bazıları diğerleri ile zıt olan farklı sonuçlara ulaşmıştır. Bu nedenle, bu çalışma hafıza sistemi ve hipokampüs üzerinde düşük yoğunlukta sigara dumanına (10-32 ppm) maruziyetin yapısal ve işlevsel olası sonuçunu ortaya çıkarmayı hedeflemiştir. YÖNTEM: Morris Su Labirenti Testinin sigara dumanı maruziyeti öncersi ve sonrası elde edilen referans zaman kayıtlarını kullanılmıştır. Bu zaman kayıtları hipokampüsün işlevsel bütünlüğünün göstergesi olarak değerlendirilmiştir. Ayrıca erkek ratların hipokampüsünün CA1 ve CA2 piramidal hücre tabakalarının fotomikrografisi çekildi ve görüntü programının manuel sayıcısına yüklendi. Sonra normal ve piknotik görünümlü hücreler sayıldı. BULGULAR: Maruz kalmış erkek ve dişi ratların maruziyet sonrası referans zaman kayıtlarındaki bozulma kontrol grubundaki bozulmaya göre daha fazlaydı. Hücre sayımı, maruz kalmış erkek ratlarda normal ve piknotik hücre popülâsyonunda anlamlı artışı ortaya koydu. SONUÇ: Bu bulgular, 10-32 ppm'lik karbon monoksit düzeyinde sigara dumanına maruziyetin ratlarda referans hafızayı bozduğunu ve erkek ratların hipokampüsünün CA1 ve CA2 piramidal hücre tabakalarındaki nörogenezi ve hücre ölümünü desteklediğini ortaya koyar.

[The Effect of Cigarette Smoke Maintained at 10-32 ppm of Carbon Monoxide on Reference Memory and Count of Pyramidal Cells of the Hippocampus of Wistar Rats.]

AIM: Numerous works relating to memory had obtained several different results, some contrasting others. Hence, the need for the current work aimed at revealing the structural and functional implication of exposure to cigarette smoke at low concentration (10-32 part per million) on the memory system, the hippocampus in particular. METHOD: The methodology involved the use of reference time records obtained from Morris water maze task before and after the exposure to cigarette smoke. These reference time records served as indicators of the functional integrity of the hippocampus. Additionally, the pyramidal cell layer of CA1 and CA2 of the hippocampus of the male rats was photomicrographed and uploaded onto the manual counter of the image software, then counted into either normal appearing or pyknotic appearing cells. RESULTS: The results revealed a detoriation in the post exposure reference time records of the exposed male and female rats compared to the lower post exposure time records obtained among the control male and female rats. The cell counting revealed a significant increase in the population of both the normal and pyknotic pyramidal cells in the exposed male rats. CONCLUSION: These findings imply that cigarette smoke exposure at 10-32 ppm of carbonmonoxide disrupts reference memory in rats - mostly in females - and supports both neurogenesis and cell death in the pyramidal cell layers of CA1 and CA2 regions of the hippocampus of male rats.

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