Blood platelets, aggregation inhibition

A contact dermatitis occurs infrequently. Because feverfew also inhibits human blood platelet aggregation, interactions are possible with antithrombotic medications such as aspirin or warfarin (Groenewegen and Heptinstall 1990). Abrupt discontinuation of feverfew by people taking it chronically for treatment of migraine can produce rebound withdrawal symptoms. These consist of migraines, anxiety, poor sleep patterns, and stiffness of the muscles and joints. 

Lawson LD, Ranson DK, Hughes BG. Inhibition of whole blood platelet-aggregation by compounds in garlic extracts and commercial garlic products. Thromb Res 1992 65 141-156. 

A group of 3-oxoisothiazolopyrimidines (164) have been patented for their ability to inhibit human blood platelet aggregation (77GEP2718707). 3,6-Dialkylisothiazolo[3,4-d]pyrimidin-4(5H)-ones (165) show useful herbicidal activity (73GEP2249099). 

Anthocyanins could act against carbon tetrachloride-induced lipoperoxi-dation. Anthocyanins could also reduce the incidences of fragility of capillaries, inhibit blood platelet aggregation, and strengthen the collagen matrix which is a component of the connective tissues [6]. 

Some 3(2//)-pyridazinones inhibit blood platelets aggregation... 

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. 

Prostaglandins Lower blood pressure Inhibit blood platelet aggregation Control inflammation Lower gastric secretions Stimulate uterine contractions Relax smooth muscles of the uterus... 

Prostacyclins Dilate blood vessels Inhibit blood platelet aggregation... 

ADENOSINE RECEPTOR AGONISTS act extra-cellularly at receptors variously known as adenosine receptors, PI purine receptors, PI receptors, P purinoceptors, or nucleoside receptors. Adenosine receptors have a wide range of mainly inhibitory actions in the body, including cardiac slowing, a fall in blood pressure, dilation of bloqd vessels, inhibition of platelet aggregation, inhibition of intestinal movements and actions within the central nervous system. 

Diterpenes (C20) can be linear as in the phytol part of chlorophyll or mono- to tetracyclic.87 Very well researched are the tricyclic taxanes of which taxol A from the Taxus baccata tree inhibits cell division and has found use in anticancer treatment. Certain labdanes inhibit blood platelet aggregation and kaurane norditer-pene glycosyl ester atractylosides from the Mediterranean thistle block the ATP/ADP translocation - such diterpenes are very toxic when ingested. Ubiquitous plant-derived kaurane-type diterpenes are the plant hormones (gibberellins) or defense substances (phytoalexins). 

What do prostaglandins and leukotrienes have to do with lipids The unsaturated fatty acid arachidonic acid is the precursor of prostaglandins and leukotrienes, compounds that have a wide range of physiological activities. Stimulation of smooth-muscle contraction and induction of inflammation are common to both classes of compounds. Prostaglandins are also involved in control of blood pressure and inhibition of blood-platelet aggregation. 

Prostaglandins in blood platelets can inhibit their aggregation. This is one of the important physiological effects of prostaglandins. 

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