Prostaglandins actions

Baker ME. Genealogy of regulation of human sex and adrenal function, prostaglandin action, snapdragon and petunia flower colors, antibiotics, and nitrogen fixation functional diversity from two ancestral dehydrogenases. Steroids 56 1991 354-360. 

Hedqvist, P. (1977). Basic mechanisms of prostaglandin action on autonomic neurotransmission. Annu. Rev. Pharmacol Toxicol, 17, 259-279... 

Another area of prostaglandin action which has been studied in detail is their role in water-retention by the kidney. The final event in urine production occurs in the terminal portion of the renal tubule where ADH... 

The enzyme system responsible for the biosynthesis of PGs is widely distributed in mammalian tissues and has been extensively studied (2). It is referred to as prostaglandin H synthase (PGHS) and exhibits both cyclooxygenase and peroxidase activity. In addition to the classical PGs two other prostanoid products, thromboxane [57576-52-0] (TxA ) (3) and prostacyclin [35121 -78-9] (PGI2) (4) are also derived from the action of the enzyme system on arachidonic acid (Fig. 1). 

These actions of aspirin are thought to result from its abiHty to reduce the production of prostaglandin formed by platelet cells without appreciably... 

Other mechanisms of action, such as potentiation of the bradykinin [58-82-2] effect, and increased production of prostaglandins... 

I. J. Koski, B. A. Jansson, K. E. Markides and M. L. Lee, Analysis of prostaglandins in aqueous solutions by supercritical fluid exti action and clrromatogi aphy , 7. Pharm. Biomed. Anal. 9 281-290 (1991). 

Bradykinin stimulates natriuresis and, through stimulation of prostaglandin synthesis, inhibits the actions of antidiuretic hormone (ADH), thereby inhibiting water retention. Bradykinin further improves insulin sensitivity and cellular glucose utilization of skeletal muscle cells in experimental models. This, however, appears not to be relevant in the clinical context. 

Dronabinol (tetrahydrocannabinol), the active principle from cannabis and synthetic cannabinoids, nabilone and levonantradol are effective in treating nausea and vomiting in cancer chemotherapy. The mode of action is unclear but appears to involve cannabinoid CBi receptors. Cannabinoids have been shown to reduce acetylcholine release in the cortex and hippocampus, and have been suggested to inhibit medullary activity by a cortical action. Inhibition of prostaglandin synthesis and release of endorphins may also be involved in the antiemetic effect. A review of trials of dronabinol, nabilone or levonantradol concluded that while the cannabinoids were superior to placebo or dopamine receptor antagonists in controlling emesis... 

Vane JR (1971) Inhibition of prostaglandin synthesis as a mechanism of action for aspirin-like drugs. Nat New Biol 231 232-235... 

PGs act locally in an autocrine or paracrine fashion in the tissues in which they are synthesized, rather than as circulating hormones, which act at a distant site. For this reason, studies localizing the enzymatic machinery, which synthesize prostaglandins, are informative with respect to the site of PG actions. PG synthesis is... 

The manner in which salicylates relieve pain and reduce inflammation is not fully understood. It is thought that the analgesic action of the salicylates is due to tiie inhibition of prostaglandins. Prostaglandins are fatty acid derivatives found in almost every tissue of the body and body fluid. Release of prostaglandin is thought... 

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