Avanços terapêuticos em cardiologia. Parte 7: prostaglandinas / Therapeutic development in cardiology. Part 7: prostaglandins

Os autores assinalam as principais indicaçöes das prostaglandinas em cardiologisa. Há dois grupos principais desta droga: vasodilatadoras - PG12,PG13 e PGE2, e vasoconstritoras - TXA2, PGE1 e PGF2alfa, mostram sua importância no mecanismo de açäo de drogas como a furosemida. As principais aplicaçöes das prostaglandinas dizem respeito a várias condiçöes: doença isquêmica, hipertensäo arterial, cardiopatia congênita, insuficiência cardíaca e cirurgia cardíaca. As prostaglandinas constituem um marco na cardiologia moderna

Interleukin 1 and receptor expression, kinetics of cyclooxygenase and synthesis of prostaglandin E2 in keratoconus cells

As inetrleukin increases secretions of prostaglandin E2 and collagenase, we have investigated the number of membrane receptors for this cytokine on keratoconus fibroblasts and determined the corresponding dissociation constant [Kd]. We have also studied kinetics of cyclooxygenase, synthesis of prostaglandins E2, interleukin 1 and collagen. The data were compared with those from human normal cornea fibroblasts. Eight normal corneas and eight keratoconus were studied. Cells were seeded in 24-well plated, at a concentration of 50,000 cells per well and cultured for 24 hours before the experiments. Increasing concentrations of 125 I labelled IL1 were added to the wells. The number of receptors for IL1 was found to be 4 fold higher for keratoconus. Consequently, synthesis of PGE2 is ten times more in keratoconus than in normal cornea cells, and collagen synthesis decreased in keratoconus. Relation between inflammatory disease and keratoconus are discussed

Aspirin thromboxane A2 and prostacyclin the effect of 100mg aspirin daily on plasma thromboxane A2 and prostacyclin levels

In the pathologic events associated with active coronary disease, alterations in the metabolisms of thromboxane A2 [TxA2] and prostacyclin [PGI2] are seen. These may result in disintegration of platelet and vascular wall reactivities accompanying coronary spasm or intravascular thrombosis, associated with myocardial cell necrosis. The main factor relevant with the above mechanisms is the decrease of TxA2/PGI2 ratio. Generally the aim in the treatment concerning these prostanoids is to establish the dose of the drug which inhibits TxA2 maximally and PGI2 minimally. This study has been performed with this aim in 10 healthy volunteers, age varying between 17 and 48. 100 mg/day aspirin's single dose and the15 days long usage of the same amount's effect have been investigated on plasma TxA2and PGI levels. Plasma values of TxB2 and 6 - keto PGF1alpha [stable metabolites of TxA2 and PGI2, respectively] have been measured with the tritium labeled radioimmunassay kits of Nen Firm [Cat. No. NEK 007 and 008, respectively]. 100 mg/day aspirin's single dose have caused inhibition on TxB2 and 6 - keto PGF2 alpha respectively as 82.3% and 58.3%. After long term usage these inhibitions were again respectively 96.8% and 85.1%. A a result, it has been found out that, after long term usage of 100 mg aspiring daily, TxB2 30.75, while 6 - keto PGF1 alpha 6.70 times were decreased compared to the control groups' mean values