Balb/C türü dişi farelerde uniseksüel gruplamanın östrus siklusu üzerine etkileri

Sosyal çevreye ait uyarıcılar farelerde östrus siklusunun frekansını ve düzenini etkiler. Kalabalık halde bırakılan dişi farelerin çoğu spontan yalancı gebelik ya da persis-tent diöstrus gösterme eğilimindedir. Bu yüzden dişi fareler arasındaki ilişkiler onların kafesleme koşullarını belirleyen önemli bir faktör olarak dikkate alınmalıdır. Bu çalışmada amacımız; Balb/c türü dişi farelerde kafes popülasyonu yoğunluğunun östrus siklusu ve vajinal sürüntü sitolojisi üzerine etkilerini incelemektir. Hayvanlar bir kafeste iki (Set I, n=40) ya da sekiz fare (Set II, n=40) olacak şekilde kafeslenerek 2 deney seti oluşturuldu. Her bir dişi farenin östrus durumu, 15 gün boyunca her sabah standart vajinal sürüntü metoduyla tespit edildi. İki dişi/kafes grubunda ortalama 4-5 günlük düzenli sikluslar gözlenirken, 8 dişi/kafes grubunda uzayan sikluslar tespit edildi. Set I grubunda her faza ait vajinal sürüntü histolojisi normal hücre popülasyonunu sergilemekte idi. Kalabalık kafes popülasyonunda ise nötrofillerden ve mukustan zengin sürüntüler elde edildi. Deney süresince Set II grubunda östrus ve proöstrus faz frekansları anlamlı oranda azalırken, diöstrus frekansı belirgin derecede artmıştı. Aynı şekilde diöstrus indeksi-nin de Set II grubunda Set I grubundan anlamlı oranda yüksek olduğu gözlendi. Sonuç olarak, elde ettiğimiz bulgular Balb/c türü dişi fareler kullanılırken, östrus senkronizasyonu için kafes yoğunluğunun 2 dişi/kafes şeklinde düzenlenmesi ile hem düzenli siklusların hem de normal vajinal sürüntü histolojisinin elde edilebileceğini göstermektedir.

Effects of unisexually grouping on the estrous cycle regulation in balb/c female mice

Stimuli from social environment influence both the frequency and regularity of the estrous cycle in the mouse. The most of the unisexually grouped females tend to show spontaneous pseudopregnancies or persistent diestrous. Therefore, relationship among the female mice should be considered as a determining factor of housing conditions in the experimental studies. We aimed to investigate the effects of density of cage population on the estrous cycle and the vaginal smear in Balb/c female mice. Two sets of animals were placed in two (Set I, n=40 ) and eight (Set II, n=40) females per cage. The estrous status of each female mouse was determined each morning for 15 days by the standard vaginal smear method. Animals showed 4-5 days regular cyles in 2/cage group while prolonged cycles was observed in 8/cage group. Histology of vaginal smears represented normal cell populations of each respective estrous cycle phases. However, smears of multiply housed mice were mostly with mucus and leucocytes. Estrous cycle was affected by showing a significant decrease in the frequency of proestrous and estrous and with concomitant significant increase in the frequency of diestrous in all the Set II females, throughout the experiment. Similarly, the diestrous index of Set II group was significantly greater than Set I group. In conclusion, these results support that cage density as two female per cage can contribute to obtain both regular estrous cycles and histology of normal vaginal smear in Balb/c female mice for synchronization of estrous.

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