Füsun TOSUN, Aymelek GÖNENÇ, Bolkan ŞİMŞEK

Comparison of the tocolytic effects of ritodrine and $Ca^{++}$ Channel blockers on serum oestradiol and progesterone levels

Bu çalışmada in vivo ovariektomi yapılan sıçanlara gonodal steroid uygulanarak deneysel gebelik oluşturuldu. Tuz diyeti ve oksitosin uygulanarak riskli gebelik tablosu oluşturmak suretiyle erken doğum ortamı hazırlandı. Erken doğumu önlemek için bir beta-mimetik olan ritodrin, Ca" kanal blokerleri olan nitrendipin ve nikardipin üç ayrı gruba verildi. Bu üç tokolitik ajanın etkileri serum estradiol ve progesteron düzeyleri tayin edilerek incelendi. Ayrıca sistolik basınç ve taşikardi de değerlendirildi.Tokolitik ilaç kullanan her üç grupta da estradiol düzeylerinde artış, progesteron düzeylerinde düşüş saptandı. Bu üç ilacın tokolitik etkili olarak kullanılabileceği, fakat ritodrinin taşikardi riski taşıdığı gözlendi. Tokolitik ajan verilmemiş riskli gebelik grubunda (hipertansif) saptanan bulgular bu grupta normal gebelik süresinin tamamlanmadığını gösterdi.

Ritodrin ile $Ca^{++}$ kanla blokerlerinin tokolitik etkilerinin serum estradiol ve progesteron düzeyleri üzerinden karşılaştırılması

Experimental pregnancy was induced with gonadal steroids in in vivo ovariectomized rats. Conditions for premature delivery were established by giving a salt-rich diet and administering oxytocin to induce high-risk pregnancy. In order to avoid early delivery, a betamimetic ritodrine and the Ca" channel blockers nitrendipine and nicardipine were administered to three separate groups. The effects of these three tocolytic agents were examined by determining serum oestradiol and progesterone levels. Additionally, systolic blood pressure was measured and tachycardia was observed.After the administration of tocolytic agents, it was observed that serum oestradiol levels were increased while there was a decrease in serum progesterone levels. These three drugs cause no difference in hormone levels and can be used as tocolytic agents; however, it was observed that ritodrine carries the risk of tachycardia. Findings in the high-risk pregnancy group (hypertensive), to which no tocolytic agent was given, showed that the normal pregnancy period had not been completed.

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