Pharmacy Exam Points (to remember)... Set 9

1. Aspirin is an irreversible inhibitor of cyclo-oxygenase enzyme.
2. Leukotriene C4 is an eicosanoid that is generated through the lipoxygenase pathway while Prostaglandin E2, Thromboxane A2, and Prostacyclin are eicosanoids that are generated through the cyclo-oxygenase pathway.
3. The prostanoid that consistently constricts blood vessels is Thromboxane A2.
4. Dysmenorrhoea (painful monthly flow) is often associated with excess production of the autacoid, prostaglandin by the endometrium.
5. Actions of prostaglandin E2 include the following, fall in blood pressure, uterine contraction, inhibition of gastric acid secretion.
6. Thromboxane A2 is a prostanoid that is a potent inducer of platelet aggregation.
7. Low doses of aspirin prolong bleeding time by selectively inhibiting synthesis of the Thromboxane A2 in the platelets.
8. Prostaglandins play pathophysiological role in the patency of ductus arteriosus, regulation of renal tubular salt absorption, and initiation of labour but they play no pathophysiological role in the ventricular remodeling after myocardial infarction.
9. Aspirin in low doses produces longlasting inhibition of platelet cyclooxygenase (COX) because platelets cannot synthesize fresh COX molecules.
10. Cysteinyl-leukotrienes (CysLTs), i.e. LT-C4, LT-D4 and LT-E4 are inflammatory mediators and potent airway- and vasoconstrictors.