Description | Prostaglandin B1 (PGB1) is a metabolite of PGE1. PGE1 is a prostanoid. Prostanoids is a term that collectively describes prostaglandins, prostacyclines and thromboxanes. Prostanoids are a subclass of the lipid mediator group known as eicosanoids. They derive from C-20 polyunsaturated fatty acids, mainly dihomo-gamma-linoleic (20:3n-6), arachidonic (20:4n-6), and eicosapentaenoic (20:5n-3) acids, through the action of cyclooxygenases-1 and -2 (COX-1 and COX-2).
PGB1does not inhibit phospholipase activity, but oligomers of PGB1 (PGBx) extracted from human neutrophils inhibit human phospholipases A2 in vitro and in situ in a dose-dependent manner; these oligomers inhibit arachidonic acid mobilization in human neutrophils and endothelial cells. One mechanism for the pharmacological effects of PGBx may be inhibition of cell-associated and extracellular phospholipase A2.
PGB1 has the ability to enhance peripheral vascular resistance and elevate blood pressure. The effect is not central in origin and apparently is not the result of changes in cholinergic or alpha-adrenoceptor sensitivity or changes in vascular smooth muscle susceptibility per se. PGB1 blocks S-phase DNA synthesis; inhibition of DNA synthesis does not appear to require elevated levels of cAMP. (PMID: 7667505, 1477202, 2129000, 2597672, 6635328)
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