It was found previously that platelet-activating factor (PAF, 1-0-alkyl-2-acetyl-sn-glycero-3-phosphocholine) is undetectable in human amniotic fluid obtained befor labor but is present in the majority of samples of amniotic fluid obrained after labor. In the present investigation, the amount of PAF in amnion tissue and the ability of this tissue to preduce PAF and respond to PAF were investigated. Amount of PAF in amnion obtained either during the second trimester of gestation or at term (before labor) were similar. After labr, however, the amount of PAF in amnion increased to 2.5-times that in amnion before labor without any discernible changes in the amount of two related glycerophospholipids viz., 1-0-alkyl-sn-dlycero-3-phosphocholine and 1-0-alkyl-2-acyl-sn-glycero-3-phosphocholine. The Ca2+-ionophore A23187, in the presence of Ca2+, caused an increase in the amount of PAF in amnion tissue disks but PAF did not appear to be released into the incubation medium. The stimulation of PAF formation by A23187 and Ca2+ was not affected by the addition of indomethacin. Addition PAF to disks of amnion tissue resulted in an increase in the concentration of prostaglandin E2 in the incubation medium. An increase in prostaglandin E2 formation of similar magnitude was induced by A23187. Based on these results it is concluded that PAF can be synthesized in amnion tissue and net production is stimulated by Ca2+. In addition, amnion is receptive to extracellular PAF and exhibits, as one response, an increased production of prostaglandin E2. © 1985.
Platelet-activating factor metabolism in human amnion and the responses of this tissue to extracellular platelet-activating factor / M. M., Billah; G. C., Di Renzo; C., Ban; C. T., Truong; D. R., Hoffman; Anceschi, Maurizio Marco; J. E., Bleasdale; J. M., Johnston. - In: PROSTAGLANDINS. - ISSN 0090-6980. - 30:5(1985), pp. 841-850.
Platelet-activating factor metabolism in human amnion and the responses of this tissue to extracellular platelet-activating factor
ANCESCHI, Maurizio Marco;
1985
Abstract
It was found previously that platelet-activating factor (PAF, 1-0-alkyl-2-acetyl-sn-glycero-3-phosphocholine) is undetectable in human amniotic fluid obtained befor labor but is present in the majority of samples of amniotic fluid obrained after labor. In the present investigation, the amount of PAF in amnion tissue and the ability of this tissue to preduce PAF and respond to PAF were investigated. Amount of PAF in amnion obtained either during the second trimester of gestation or at term (before labor) were similar. After labr, however, the amount of PAF in amnion increased to 2.5-times that in amnion before labor without any discernible changes in the amount of two related glycerophospholipids viz., 1-0-alkyl-sn-dlycero-3-phosphocholine and 1-0-alkyl-2-acyl-sn-glycero-3-phosphocholine. The Ca2+-ionophore A23187, in the presence of Ca2+, caused an increase in the amount of PAF in amnion tissue disks but PAF did not appear to be released into the incubation medium. The stimulation of PAF formation by A23187 and Ca2+ was not affected by the addition of indomethacin. Addition PAF to disks of amnion tissue resulted in an increase in the concentration of prostaglandin E2 in the incubation medium. An increase in prostaglandin E2 formation of similar magnitude was induced by A23187. Based on these results it is concluded that PAF can be synthesized in amnion tissue and net production is stimulated by Ca2+. In addition, amnion is receptive to extracellular PAF and exhibits, as one response, an increased production of prostaglandin E2. © 1985.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
