Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00790 (PGA)
 2,475 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We examined the hypothesis that the vascular abnormalities of Bartter's syndrome are due to excess production of prostaglandin. Balance studies and vascular reactivity studies were performed before and after indomethacin (200 mg/day) in a patient with well-documented Bartter's syndrome. During indomethacin, potassium balance became positive, serum potassium rose from 2.1--3 mEq/1 in the absence of potassium supplementation, plasma renin activity decreased from 55--3.2 ng/day and peripheral plasma PGA-like activity fell from 1460 +/- 220 to 456 +/- 71 pg/ml. Before indomethacin, forearm vasoconstrictor responses to brachial arterial infusions of angiotensin II, norepinephrine and to neurogenic reflex stimulation elicited by lower body suction were greatly depressed compared to those of normal subjects. During indomethacin these responses were restored to normal. The dose of intravenous angiotensin II required to increase diastolic blood pressure 20 mm Hg decreased from 160--30 ng/kg/min. These data support the hypothesis that the vascular insensitivity to exogenous angiotensin II, norepinephrine and to neurogenic reflex stimulation observed in this patient with Bartter's syndrome is due to excess prostaglandin. Moreover, stimulation of the renin-angiotensin-aldosterone system in this syndrome appears to be a compensatory adaptation to excess prostaglandin production.
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PMID:Effects of indomethacin on the vascular abnormalities of Bartter's syndrome. 67 46

The derivatization of prostaglandins of the A series with 1:1 mixtures of bis-(trimethylsilyl)trifluoroacetamide and nitrogen-containing non-aromatic heterocyclics such as piperidine, pyrrolidine, morpholine and hexamethylenimine (1--4 h at 60--70 degrees C) gives new types of derivatives, designated as 11-heterocycle, 9-enol PGA (TMS)3. These derivatives show very simplified and characteristic mass spectral patterns strikingly dominated by a common [M-173]+ fragment ion and easily detectable by selected ion monitoring. This feature allows the concurrent analytical detection of both prostaglandin A's and 19-hydroxy prostaglandin A's in biological samples. In this case 2 ml samples of human semen were extracted by direct ultrafiltration on a Pellicon membrane with a nominal molecular weight limit of 1000. The prostaglandins in the approximately or equal to 1.6 ml of ultrafiltrate thus obtained were recovered in ethyl acetate, derivatized as indicated above and detected by monitoring of the corresponding [M-173]+ ions.
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PMID:New derivatives of prostaglandin A1 and specific detection of prostaglandin A's and 190hydroxylated prostaglandin A's in human semen. 70 54

The contractile response of the isolated testicular capsule to acetylcholine, norepinephrine and prostaglandins (A-2, E-1 and F-2alpha) was related to the age of the rat. Norepinephrine and PGA-2 caused an increased capsular response between 45 and 60 days of age, the time at which spermiogenesis begins. It is suggested that the activity of the testicular capsule is involved in the transport of non-motile spermatozoa from the testis and into the epididymis.
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PMID:Age-related differences in the response of the isolated testicular capsule of the rat to norepinephrine, acetylcholine and prostaglandins. 72 75

Human volunteers were exposed in an experimental chamber to styrene (4 or 8 hours at 40 to 200 ppm) in order to obtain a quantitative relationship between exposure and urinary elimination of the metabolites mandelic and phenylglyoxylic acids (MA and PGA). For the analysis of PGA a new GC-method was used, based on reductive transformation of the relatively instable PGA into MA, which is stable enough for shipping and handling until final processing. The analysis of the post-exposure elimination shows that spot urine sampled in the morning after exposure and analysed for the sum of MA and PGA is the most reliable index for reflecing a preceding exposure to styrene.
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PMID:Biological monitoring of exposure to styrene by analysis of combined urinary mandelic and phenylglyoxylic acids. 73 98

Since their discovery more than 40 years ago, PGs have been shown to be present in many tissues. The 10 members of this family (PGA-PGI and TxA) that have been identified to date have been noted to have a wide variety of pharmacologic actions. Frequently, the actions of one PG are in direct opposition to those of another. This has led to the theory that PGs play an important role in maintaining homeostasis in many organ systems. Evidence accumulated indicates a major role for PGs in the regulation of blood pressure, the autonomic nervous system, blood flow and platelet aggregation. This is in addition to specific actions on other tissues such as the CNS and reproductive system. A summary of PG actions in humans is contained in Table 1. Unfortunately, the PGs have not been as useful therapeutically as originally hoped. Currently, they are being used to induce labor and to maintain the patency of the PDA. However, they still hold much promise and with the development of synthetic analogues and specific synthesis inhibitors, they should live up to this promise in the future.
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PMID:Prostaglandins: an overview. 74 49

The role of PGA on the release of renin in the anesthetized dog has been studied. The infusion of prostaglandin for 60 minutes at a dose unable to cause pressor modifications (2 microgram/kg/min) was shown to increase the plasma renin activity (PRA); this effect was inhibited by propranolol and strengthened by aminophylline.
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PMID:Effect of prostaglandin A on renin secretion in the dog. 74 59

It may be concluded that the conversion of PGA to DPGA plays a key role in induction and in the regulation of cycle activity. The high concentrations of PGA in actively photosynthesizing chloroplasts reflect this role and the control exerted by adenylate ratios. Thus the cycle can operate at its maximum rate only in the presence of high PGA and low ribulose 5-phosphate concentrations. Once induction is complete, the reductive pentose phosphate pathway will continue to function at its maximum rate if sink activity within the cytoplasm makes available sufficient Pi to support rapid export of triose phosphate. If triose phosphate tends to build up in the straoma, it will favor pentose monophosphate accumulation. A relative excess of ribulose 5-phosphate would, in turn, inhibit PGA reduction (and hence its own formation) by drawing too heavily on the available ATP.
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PMID:Regulation of photosynthetic carbon assimilation. 74 10

Absorbable corneal sutures of PGA monofilaments were tested in rabbit eyes. Compared to chromic collagen 8/0 the sutures were tolerated well, but the absorption time of 14.6 days is considered as being too short for corneal surgery.
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PMID:Absorption time of PGA monofilaments and collagen 8/0 in corneal sutures. 79 Sep 12

In addition to its well known prohypertensive role in various states of experimental and human hypertension, the kidney has also been shown to exert an antihypertensive "endocrine" function. According to this hypothesis, certain forms of experimental and human hypertension might not solely be the result of an excess in the activity of such renal pressor systems as the renin-angiotensin system and the sympathetic nervous system, but might also result from an absolute or relative deficiency of intra-renal vasodilator antihypertensive factors which might allow pressor systems to act unopposed to produce peripheral arteriolar vasoconstriction and sustained hypertension. At least four factors have been characterized in the kidney of various animal species and man which might be responsible for such an antihypertensive function. These are (1) the renomedullary prostaglandins (PGs), (2) the renomedullary antihypertensive neutral lipid, (3) antirenin phospholipid and (4) the renal kinins. This review is restricted to an examination of the possibility that the vasodepressor renomedullary prostaglandins (PGA and/or PGE) may, at least in part, mediate the so-called antihypertensive function of the kidney and participate in the regulation of renal blood flow and natriuresis by physiologic antagonism of various renal vasoconstrictor stimuli such as the renal renin-angiotensin and the sympathetic nervous systems.
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PMID:Renal prostaglandins and the regulation of blood pressure and sodium and water homeostasis. 79 89

Experimental data now strongly suggest that the PGs, by nature of their natural local occurrence and destruction, powerful effects on, and release from lung tissue are important in regulating both pulmonary homeostasis and dysfunction. Laboratory studies on their activity, potency, duration, preferred route of administration, mechanism and possible antiallergic effects, have been largely substantiated in humans. Structure activity studies on a large number of congeners of PGE, PGF, and PGA emphasize the critical importance of stereochemistry and various substituent groups on biologic activity in the lung.
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PMID:Actions of prostaglandins on the respiratory tract of animals. 82 48


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