6- Keto-PGF

TP receptors were fotmd to be highly expressed on thymocytes (41,42), and TP receptor agonists stimulated apotosis of these cells (42). Since phagocytic cells of the thymic reticulum produced TXAj, along with PGEj and 6-keto-PGF, , and they were shown to regulate thymocyte proliferation in vitro (43), TXAj may exert a negative control on thymocyte proliferation. 

Margalit et al. [48] reported the simultaneous quantitative analysis of 14 eicosanoids in biological samples using column-bypass negative-ion ESI-MS in SRM mode. Detection limits ranged from 0.5 pg for TXBj to 10 pg for 6-keto PGF, . 

Epoprostenol (Prostaglandin I, Prostacyclin). Epoprostenol is the name used to describe a prostacyclin formulation for exogenous administration. This drug has a very short half-life in the body and is rapidly broken down to 6-keto-PGF . Prostacyclin is a vasodilator and potent inhibitor of platelet aggregation and is used to treat pulmonary hy-... 

Collecting tubules from the rabbit renal papillae synthesize 6-keto-PGF from AA.98 1 ... 

Prostacyclin (PGI2) is an active and unstable metabolite (rj/2 = 3 minutes at 37°C and pH 7.5) formed from PGH2 by prostacyclin synthase. PGI2 has a double-ring structure and is converted by nonenzymatic hydrolysis to 6-keto-PGF] (Figure 18-22). 

Exhibiting a pattern of eicosanoid excretion noted in essential hypertension, lead-exposed workers showed an increase in TxB2 and a decrease in PGE2 and 6-keto-PGF] in fhe mine [63]. In contrast to the reabsorpfive defect of acute lead nephropathy, saturnine gout is characterized by renal retention of uric acid. The clearance and maximal secretion rate for para-aminohippurate have been found to be variable in patients with occupational lead nephropathy. A reduced maximal reabsorpfive rate for glucose has been reported, but simultaneous, matched controls were not obtained [69]. 

The degradation of PGI (t of 3 minutes) apparently begins with its spontaneous hydrolysis in blood to 6-keto-PGF The metabolism of this compound involves the same steps as those for PGE and PGF, . ... 

Higher capacity to form prostaglandins have been noted in some brain areas, notably in the hippocampus, the median eminence, pineal gland and pituitary [206,212]. In the rat and human cerebral blood vessels a high capacity for PGI2 production was noted [208,213,214]. It is believed that high levels of 6-keto-PGF, in cerebrospinal fluid could originate from vascular tissue [215]. 

PGF, [54] a capacity which is not restricted to adult animals as organs and blood vessels from fetal and neonatal animals have also been shown to produce 6-keto PGF, [55],... 

It is not unexpected that PGIj or 6-keto PGF, should be present in amniotic fluid since uteroplacental tissues are capable of synthesising these products. In a recent report Ylikorkala et al. [125] and Bodzenta et al. [126] measured the concentrations... 

Cerebrospinal fluid 6-keto-PGF, pg/mi 120 -3600 (F) Man GC-MS normal cerebral trauma, epilepsy. 128... 

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