Blood platelet aggregation, effect

Prostaglandins have many effects they lower blood pressure, affect blood platelet aggregation, affect kidney function and stimulate uterine contractions. 

Each eicosanoid is associated with specific types of biological activity (Table 29.4). In some cases, the effects oppose one another. For example, thromboxanes are vasoconstrictors that trigger blood platelet aggregation, whereas prostacyclins are vasodilators that inhibit platelet aggregation. The levels of these two eicosanoids must be in the right balance for cells to function properly. 

Vallance P, Benjamin N, Collier J. The effect of endothelium-derived nitric oxide on ex vivo whole blood platelet aggregation in mai. Eur J Clin Pharmacol 1992 42 37-41. 

Skin sweat, piio motor Male ejaculation Blood platelet aggregation Metabolic effect hyperkalaemla 1 Metabolic effects hypokalaemia (p ) hepatic glycogenolysis (p ) lipolysis (P. P )... 

Serotonin (5-hydroxytryptamine, 5-HT) is synthesised in enterochromaffin cells, largely in the gut, and also extensively taken up into blood platelets from which it is released to have vascular effects. It has complex effects on the cardiovascular system, varying with the vascular bed and its physiological state it generally constricts arterioles and veins and induces blood platelet aggregation it stimulates intestinal and bronchial smooth muscle. Carcinoid tumours secrete serotonin and symptoms may be benefited by serotonin antagonists, e.g. cyproheptadine, methysergide and sometimes by octreotide (see Index). It is a neurotransmitter in the brain. 

Protopine was shown to exhibit an inhibitory action on blood platelet aggregation induced by collagen, arachidonic acid, and ADP in vitro. In addition, protopine demonstrated equal or superior inhibitory effects when compared with that of the standard drugs acetylsalicylic acid or dipyridamole [266]. 

BIOLOGICAL ACTIONS Gastrointestinal smooth muscle Reproductive smooth muscle Respiratory smooth muscle Cardiovascular system Blood platelet aggregation Metabolic effects... 

Saluk-Juszczak, J., B. Olas, I. Pawlaczyk, R. Gancarz, and B. Wachowicz. 2007. Effects of the extract from Conyza canadensis on human blood platelet aggregation. Gen. Physiol. Biophys. 26(2) 150-152. 

Intrazole (BL-R743), aspirin, and phenylbutazone effectively inhibited rabbit platelet aggregation in both vitro and in vivo screens. 5 Htiman blood platelet aggregation was inhibited by aspirin and other NAA. - In all these cases the compounds are considered to work by inhibiting the release mechanism. 

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