Thyroid control of sarcolemmal Na+/Ca2+ exchanger and SR Ca2+-ATPase in developing rat heart.

Thyroid hormone (TH) levels increase in the postnatal life and are essential for maturation of myocardial Ca2+ handling. During this time, the sarcolemmal (SL) Na+/Ca2+ exchanger (NCX) function decreases and the sarcoendoplasmic reticulum (SR) Ca2+-ATPase (SERCA2) function increases. We examined the effects of postnatal hypo- or hyperthyroidism on NCX and SERCA2 in rat hearts.

Morphology of non-ventilated transplanted rat lungs.

Morphological changes in lung tissue of heterotopic heart-lung transplants have been studied 28 days following transplantation in 20 rats. Lung tissue showed disperse haemorrhagic necrosis often sparing bronchi and branches of pulmonary artery and conspicuous accumulation of bronchial secretion. Partial disappearance of cardiac muscle cells from the walls of pulmonary veins has been ascribed to tissue hypoxia.

Transplantation-induced atrophy of normal and hypertrophic rat hearts: effect on cardiac myocytes and capillaries.

Changes in tissue structure of hearts undergoing atrophy following heterotopic isotransplantation were studied. Both normal and hypertrophic hearts were used, originating from male and female rats. Aortic constriction produced in newborn rats, resulted in an 86 and 155% increase of left ventricular mass in male and female rats, respectively.

Myocardial fibrosis and right ventricular function of heterotopically transplanted hearts in rats treated with cyclosporin.

The aim was to determine whether treatment of rats with cyclosporin A (CsA) leads to deleterious side effects on heterotopically iso- or allotransplanted hearts when compared with recipient native in situ hearts. Four experimental groups were employed: inbred (Lewis) rats receiving either no immunosuppression or CsA at a dose of 15 mg.kg-1 per day for 7 days after surgery, and outbred (Wistar) rats receiving CsA at the same daily dose for either 7 or 21 days.

The effect of AT1 receptor antagonist on chronic cardiac response to coronary artery ligation in rats.

Objective: The aim was to study the effect of the AT1 receptor antagonist losartan on hemodynamic and morphometric changes following experimental infarction.

Methods: Experimental infarction was produced in adult male rats by ligating the coronary artery. Treatment with losartan was compared to untreated controls, in rats with experimental infarction and sham-operated animals.