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    Changes in the size distribution of goat steroidogenic luteal cells during pregnancy
    (Elsevier Science Bv, 2003) Arikan, S; Yigit, AA
    Experiments were conducted to investigate the size distribution of goat steroidogenic luteal cells throughout pregnancy. Corpora lutea were collected from very early (<6 weeks), early (6-8 weeks), middle (9-14 weeks) or late (15-18 weeks) stages of pregnancy. Luteal tissue was dissociated into single-cell suspension by enzyme treatments. Cells were stained for 3beta-hydroxysteroid dehydrogenase (3beta-HSD) activity, a marker for steroidogenic cells. The steroidogenic cells covered a wide spectrum of size ranging from 5 to 45 mum in diameter. There was a significant increase in mean cell diameter (P > 0.01) as pregnancy progressed. Mean diameter of 3beta-HSD positive cells increased from 14.73 +/- 0.35 mum in the corpus luteum of very early pregnancy to 24.20 +/- 0.45 mum in the corpus luteum of late pregnancy. The ratio of large (>20 mum in diameter) to small (5-20 mum in diameter) luteal cells was 0.28:1.0 in very early pregnancy, with the 7.5-15 mum cell size class being dominant. However, the ratio of large-to-small luteal cells was increased to 1.77:1.0 mum as pregnancy advanced and 25-35 mum cell sizes became predominant. It is likely that small luteal cells could develop into large cells as pregnancy progresses. Development of pregnancy is also associated with an increase in size of steroidogenic luteal cells. (C) 2002 Elsevier Science B.V. All rights reserved.
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    Effect of pre-haemolytic concentrations of alpha, beta and gamma cyclodextrins on the osmotic fragility of dog erythrocytes
    (Ecole Nationale Veterinaire Toulouse, 2004) Arikan, S; Yigit, AA; Zengin, N
    Knowledge of the adverse effects of cyclodextrins on erythrocytes is important in view of the growing number of their potential applications in food, cosmetic, drug and chemical industries to increase aqueous solubility and stability, and reduce or eliminate the unpleasant taste and smell of many products. The experiment was conducted to examine the effect of pre-haemolytic concentrations of alpha-, beta- and gamma-cyclodextrins on the osmotic fragility of erythrocytes. Blood samples collected from 8 healthy Turkish Kangal dogs were analysed within 3 It of collection. Erythrocyte suspensions were mixed with various concentrations of alpha-, beta-, or gamma-cyclodextrins. The mixtures were then incubated for 30 min at 37 degreesC and osmotic fragility of erythrocytes was measured. Incubation of the erythrocyte suspensions with the all three cyclodextrins induced a dose-dependent increase in the osmotic fragility of erythrocytes. Initial haemolysis (10%) in alpha-, beta-, and gamma-cyclodextrin treated groups was at 8, 4 and 46 mM cyclodextrin concentrations, respectively. In conclusion, these results indicate that pre-haemolytic concentrations of all three cyclodextrins studied might induce membrane disruption, that may cause removal of membrane components from erythrocytes. When cyclodextrins are even used in a pre-haemolytic concentrations, it might reduce life span of erythrocytes.