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Progesterone P4 is an endogenous steroid and progestogen sex hormone progesterone adenoma prostatico in the menstrual cyclepregnancyand embryogenesis of humans and other species. Progesterone has a variety of important functions in the body. It is also a crucial metabolic intermediate in the production of other endogenous steroidsincluding the sex hormones and the corticosteroidsand plays an important role in brain function as a neurosteroid.
In addition to its role as a progesterone adenoma prostatico hormone, progesterone is used as a medicationfor instance in menopausal hormone therapy ; for information on progesterone adenoma prostatico as a medication, see the progesterone medication article.
It was first described in Progesterone is the most important progestogen in the body. Since eggs release progesterone, sperm may use progesterone as a homing signal to swim toward eggs chemotaxis. As a result, it has been suggested that substances that block the progesterone binding site on CatSper channels could potentially be used in male contraception. Progesterone has a number of physiological effects that are amplified in the presence of estrogens.
Estrogens through estrogen receptors ERs induce or upregulate the expression of the PR. Elevated levels of progesterone potently reduce the sodium-retaining activity of aldosterone, resulting in natriuresis and a reduction in extracellular fluid volume.
Progesterone withdrawal, on the other hand, is associated with a temporary increase in sodium retention reduced natriuresis, with an increase in extracellular fluid volume due to the compensatory increase in aldosterone production, which combats the blockade of the mineralocorticoid receptor by the previously elevated level of progesterone.
Progesterone has key progesterone adenoma prostatico via non-genomic signalling on human sperm as they migrate through the female tract before fertilization occurs, though the receptor s as yet remain unidentified. Progesterone is sometimes called the "hormone of pregnancy ",  and it has many roles relating to the development of the fetus:. The fetus metabolizes placental progesterone in the production of adrenal steroids.
Progesterone plays an important role in breast development in women. In conjunction with prolactinit mediates lobuloalveolar maturation of the mammary glands during pregnancy to allow for milk production and thus lactation and breastfeeding of offspring progesterone adenoma prostatico parturition childbirth. Progesterone also appears to be involved in the pathophysiology of breast cancerthough its role, and whether it is a promoter or inhibitor of breast progesterone adenoma prostatico risk, has not been fully elucidated.
The estrogen receptoras well as the progesterone receptorhave been detected in the skinincluding in keratinocytes and fibroblasts. Hormone replacement therapy, consisting of systemic treatment with estrogen alone or in combination with a progestogen, has well-documented and considerable beneficial effects on the skin of postmenopausal women.
Progesterone and its neurosteroid active metabolite allopregnanolone appear to be importantly involved in libido in females. Diana Fleischmanprogesterone adenoma prostatico the University of Portsmouthand colleagues looked for a relationship between progesterone adenoma prostatico and sexual attitudes in 92 women.
Their research, published in the Archives of Sexual Behavior found that women who had higher levels of progesterone progesterone adenoma prostatico higher on a questionnaire measuring homoerotic motivation. They also found that men who had high levels of progesterone were more likely to have higher homoerotic motivation scores after affiliative priming compared to men with low levels of progesterone.
Progesterone, like pregnenolone and dehydroepiandrosterone DHEAbelongs to an important group of endogenous steroids called neurosteroids. It can be metabolized within all parts of the central nervous system. Neurosteroids are neuromodulatorsand are neuroprotectiveneurogenicand regulate neurotransmission and myelination. Previous studies have shown that progesterone supports the normal development of neurons in the brain, and that the hormone has a protective effect on damaged brain tissue.
It has been observed in animal models that females have reduced susceptibility to traumatic brain injury and this protective effect has been hypothesized to be caused by increased circulating levels of estrogen and progesterone in females. The mechanism of progesterone protective effects may be the reduction progesterone adenoma prostatico inflammation that follows brain trauma and hemorrhage.
Damage incurred by traumatic brain injury is believed to be caused in part by mass depolarization leading to excitotoxicity. One way in which progesterone helps to alleviate some of this excitotoxicity is by blocking the voltage-dependent calcium channels that trigger neurotransmitter release. Another method for reducing the excitotoxicity is by up-regulating the GABA Aa widespread inhibitory neurotransmitter receptor. Progesterone has also been shown to prevent apoptosis in neurons, a common consequence of brain injury.
Not only does progesterone help prevent further damage, it has also been shown to aid in neuroregeneration. Animal studies show that progesterone treatment leads to a decrease in edema levels by increasing the concentration of macrophages and microglia sent to the injured tissue. Progesterone adenoma prostatico addition, progesterone was observed to have antioxidant properties, reducing the concentration of oxygen free radicals faster than without. Progesterone enhances the function of serotonin receptors in the brain, so an excess or deficit of progesterone has the potential to result in significant neurochemical issues.
Progesterone adenoma prostatico provides an explanation for why some people resort to substances that enhance serotonin activity such as nicotinealcoholand cannabis when their progesterone levels fall below optimal levels.
Progesterone makes women less competitive. In mammals, progesterone, like all other steroid progesterone adenoma prostaticois synthesized from pregnenolonewhich itself is derived from cholesterol. This vicinal diol progesterone adenoma prostatico then further oxidized with loss of the side chain starting at position C22 to produce pregnenolone.
This reaction is catalyzed by cytochrome Pscc. The conversion of pregnenolone to progesterone takes place in two steps. Androstenedione can be converted to testosteroneestroneand estradiol. Pregnenolone and progesterone can also be synthesized by yeast.
The metabolism of progesterone is rapid and extensive and occurs mainly in the liver   though enzymes progesterone adenoma prostatico metabolize progesterone are also expressed widely in the brainskinand various other extrahepatic tissues.
Progesterone adenoma prostatico women, progesterone levels are relatively low during the preovulatory phase of the menstrual cyclerise after ovulationand progesterone adenoma prostatico elevated during the luteal phaseas shown in diagram below. If pregnancy occurs, human chorionic gonadotropin is released maintaining progesterone adenoma prostatico corpus luteum allowing it to maintain levels of progesterone.
Progesterone adenoma prostatico a decrease in progesterone levels is critical for the initiation of labor has been argued and progesterone adenoma prostatico be species-specific. After delivery of the placenta progesterone adenoma prostatico during lactation, progesterone levels are very low. Progesterone levels are low in children and postmenopausal women. Blood test results should always be interpreted progesterone adenoma prostatico the reference ranges provided by the laboratory that performed the results.
Example reference ranges are listed below. Progesterone is produced in high amounts in the ovaries by the corpus luteum from the onset of puberty to menopauseand is also produced in smaller amounts by the adrenal glands after the onset of adrenarche in both males and females.
To a lesser extent, progesterone is produced in progesterone adenoma prostatico tissueespecially in the brain, and in adipose fat tissueas well. During human pregnancyprogesterone is produced in increasingly high amounts by the ovaries and placenta. At first, the source is the corpus luteum that has been "rescued" by the presence of human chorionic gonadotropin hCG from the conceptus.
However, after the 8th week, production of progesterone shifts to the placenta. The placenta utilizes maternal cholesterol as the initial substrate, and most of the produced progesterone enters the maternal circulation, but some is picked up by the fetal circulation and used as substrate for fetal corticosteroids.
An additional animal source of progesterone is milk products. After consumption of milk products the level of bioavailable progesterone goes up. In at least one plant, Juglans regiaprogesterone has been detected. Dioscorea mexicana is a plant that is part of the yam family native to Mexico.
Another plant that progesterone adenoma prostatico substances readily convertible to progesterone is Dioscorea pseudojaponica native to Taiwan. Research has shown that the Taiwanese yam contains progesterone adenoma prostatico — steroids that can be converted to diosgenin and thence to progesterone.
Many other Dioscorea species of the yam family contain steroidal substances from which progesterone can be produced. Among the more notable of these are Dioscorea villosa and Dioscorea polygonoides. One study showed that the Dioscorea villosa contains 3. Progesterone is used as a medication. It is used in combination with estrogens mainly in hormone progesterone adenoma prostatico for menopausal symptoms and low sex hormone levels in women.
Progesterone is a naturally occurring pregnane steroid and is also known as pregnene-3,dione. An economical semisynthesis of progesterone from the plant steroid diosgenin isolated from yams was developed by Russell Marker progesterone adenoma prostatico for the Parke-Davis pharmaceutical company.
Additional semisyntheses of progesterone have also been reported progesterone adenoma prostatico from a variety of steroids. For the example, cortisone can be simultaneously deoxygenated at the C and C position by treatment with iodotrimethylsilane in chloroform to produce keto-progesterone ketogestinwhich in turn progesterone adenoma prostatico be reduced at position to yield progesterone. Progesterone can also be made from the stigmasterol found in soybean oil also.
Percy Julian. A total synthesis of progesterone was reported in by W. The ylide 8 is reacted with an aldehyde to produce progesterone adenoma prostatico alkene 9. The ketal protecting groups of progesterone adenoma prostatico are hydrolyzed to progesterone adenoma prostatico the diketone 10which in turn is cyclized to form the cyclopentenone The ketone of 11 is reacted with methyl lithium to yield the tertiary alcohol 12which in turn progesterone adenoma prostatico treated with acid progesterone adenoma prostatico produce the tertiary cation This step resembles the cationic cyclization reaction used in the biosynthesis of steroids and hence is referred to as biomimetic.
In the next step the enol orthoester is hydrolyzed to produce the ketone The cyclopentene A-ring is then opened by oxidizing with ozone to produce Finally, the diketone 17 undergoes an intramolecular progesterone adenoma prostatico condensation by treating with aqueous potassium hydroxide to produce progesterone.
The hormonal action of progesterone was discovered infollowing that of estrogen in Chemical synthesis of progesterone from stigmasterol and pregnanediol was accomplished later that year. The use of progesterone in tests dog breeding to pinpoint ovulation is becoming more widely used.
There are several tests available but the most reliable test is a blood test with blood drawn by a veterinarian and sent to a lab for processing. Results can usually be obtained with 24 to 72 hours. The rationale for using progesterone tests is that increased progesterone adenoma prostatico begin in close proximity to preovulatory surge in gonadotrophins and continue through ovulation and estrus. When progesterone levels reach certain levels they can signal the stage of estrus the female is.
Prediction of birth date of the pending litter progesterone adenoma prostatico be very accurate if ovulation date is known.
Puppies deliver with a day or two of 9 weeks gestation in most cases. It is not possible to determine pregnancy using progesterone tests once a breeding has taken place however. This is due to the fact that, in dogs, progestrone levels remain elevated throughout the estrus period. From Wikipedia, the free encyclopedia. This article is about progesterone as a hormone. For its use as a medication, see progesterone medication.