Prostaglandins (prostanoid acid) is formed by transformation of unsaturated fatty acids , some of them are being investigated for their role in follicle maturation ovarian, being therefore potential contraceptive natural substance is a mixture of fatty substances found in semen of ram and man . Have direct effects on relaxation and stretching of muscles nonvascular smooth (uterus).
The mechanism by which luteolysis occurs mediated by PGs is not known. But you may have a local effect related to decreased vascular flow luteum or by direct inhibition synthesis of progesterone.
Prostaglandins play an active role in identifying prostate disease and kidney. They are active in bronchial asthma in ovulation, arthritis, glaucoma and has effects on immune system. Aspirin and indomethacin inhibit action of PG's. Prostaglandins, thromboxane are
Prostaglandins must exert its effect on cells and the adjacent home, acting as hormones autocrine and paracrine being destroyed in the lungs . Actions are many and some are practical, such as PGE1, which is used clinically to keep open the ductus arteriosus in children with congenital heart ( alprostadil) and for the treatment or prevention of gastroduodenal ulcer ( misoprostol). PGE2 (dinoprostone ) is used as oxytocin in labor induction , the expulsion of dead fetus and the treatment of hydatidiform or spontaneous abortion .
hydatidiform
can summarize the functions of prostaglandins in four points:
- spoke in the inflammatory response: vasodilation, increased permeability of the tissue allowing the passage of leukocytes, antiplatelet , stimulation of pain nerve endings.
- cause contraction of smooth muscle . This is especially important in the woman's uterus. In the semen human There are small amounts of prostaglandins to promote uterine contraction and hence the ascent of sperm to uterine tubes (fallopian tubes) . Similarly, are released during menstruation to favor the shedding of endometrial . Thus, menstrual cramps are often treated with inhibitors of prostaglandin release.
- spoke in regulating body temperature.
- control the fall in blood pressure to promote the elimination of substances in the kidney .
Prostaglandins and NSAIDs
Since prostaglandins (PG) are involved in inflammatory responses by stimulating the nerve endings of pain, NSAIDs ( NSAIDs) such as aspirin, act by inhibiting cyclooxygenase and thus the production of PG. Moreover, prostaglandins are involved in maintaining the integrity and proliferation of gastric mucosa, to assure an adequate blood supply. The gastric mucosa is one of the mechanisms of protecting the stomach against aggressive agents such as hydrochloric acid and pepsin. Then, NSAIDs, by inhibiting PGs left to the gastric mucosa vulnerable to stomach acid and increases the risk of erosions and ulcers.
Prostaglandins and cancer.
in prostaglandin synthesis primarily involves two enzymes: cyclooxygenase 1 (COX-1) and cyclooxygenase 2 (COX-2). In certain pathological processes, such as inflammations and neoplasias, there is an overexpression of COX-2 enzyme, that catalyzes prostaglandin PGE2 stimulates the angiogenesis and tumor progression. Nonsteroidal anti-inflammatory drugs (NSAIDs ) reduce the risk of cancer such as breast cancer of colon and prostate , especially selective inhibitors of COX-2 as celecoxib, although yet to be confirmed in clinical trials .
now know that these substances are found in all tissues of mammals and body fluids are found in almost all cells of the body except red blood cells. For three years they were forgotten until in 1 960 was able to crystallize Bergstrom prostaglandins PGE and PGF. Five years later the Medullina was isolated from the rabbit renal medulla, identified today with the PGA.
The latest research have to do with the inhibition of the action of prostaglandins by drugs such as aspirin and indomethacin
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