Erman OR, Tülay BAKIREL, Utku BAKIREL, Güven KASIKCI

Hemodynamic effects of hypothyroidism induced by administration of methimazole to euthyroid dogs

Bu araştırma, methimazol'ün ötroid köpeklerin kardiak fonksiyonlarının invaziv parametreleri üzerine olası etkilerinin saptanması amacıyla yapıldı. Çalışmada on adet ötroid köpek kullanıldı. Methimazol (30 mg/kg) uygulanmasından önce ve sekiz hafta sonra serum $T_4, T_3$ ve TSH konsantrasyonları ve sol ventrikülün sistolik (LVSP) ve diyastolik basınçları (LVDP), kasılma (LVCT) ve gevşeme zamanı (LVRT) ölçüldü. Sekiz haftanın sonunda TSH konsantrasyonu önemli oranda artarken, serum T4 ve T3 konsantrasyonları, LVSP ve LVDP önemli bir şekilde azaldı. Bununla birlikte LVCT deki artış önemli değildi. Kontrol ve hipotroid köpeklerin LVRT arasında farklılık gözlenmedi. Elde edilen veriler, methimazol'ün köpeklerde serum triod horman konsantrasyonlarının yanısıra sol ventrikül basınçlarında da önemli değişikliklere neden olduğunu gösterdi.

Köpeklerde methimazol uygulanmasıyla oluşan hipotiroidizmin hemodinamik etkileri

This study was carried out in order to determine the possible effects of methlmazole upon the invasive parameters of the cardiac functions of the dogs. Ten dogs was used in this study. In the begining of the study and 8 weeks after orally administration of methimazole (30 mg/kg), serum $T_4, T_3$ and TSH concentrations and contraction (LVCT) and relaxation times (LVRT), systolic (LVSP) and diastolic pressures (LVDP) of left ventricle were measured. After weeks, serum T4, T3 concentrations, LVSP and LVDP were significantly decreased, while TSH concentrations was significantly increased. However, increasing in the LVCT was no important. No difference was observed between the LVRT of healty and hypothroid dogs. The results of the present study suggested that methimazole caused significant changes in serum thyroid hormone concentrations as well as the left ventricle pressures of dogs.

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