Secretory characteristics and viability of human term placental tissue after overnight cold preservation.

Collection of human term placentae for research purposes is generally limited during working hours. Preserving placental tissue overnight might help to postpone experiments and, by extent, to increase material availability. In this study, fragments from normal placentae were incubated at 37 degrees C either immediately after delivery or after preservation at 4 degrees C in a HEPES-buffered solution or in a Roswell Park Memorial Institute (RPMI) 1640 culture medium.

Alkaline phosphatase activities in normal and denervated, slow and fast rat muscles. Bearing on the possible participation of the enzyme in the transmembrane transport of phosphate ions.

Alkaline phosphatase (AP) activities are present in rat gastrocnemius:48.7, plantaris: 68.9, tibialis anterior: 69.

Alkaline phosphatase activities in human amniotic fluid, chromatographic separation of the foetal intestinal component.

Hydrophilic gel permeation chromatography of 14-36 wk human amniotic fluid on Fractogel columns divides the total alkaline phosphatase (AP) activity in a higher and a lower mol wt zones. Differential inhibition testing, isoelectric focusing, cellulose acetate, agarose and polyacrylamide gel electrophoreses before and after neuraminidase treatment show the higher mol wt zone to be homogeneous and to be made of the higher mol wt foetal intestinal isoenzyme form whereas the lower mol wt zone represents an unresolved mixture of hepatic, placental and lower mol wt foetal intestinal isoenzymes. In the early stages of pregnancy, the activity associated with the higher mol wt zone outweighs by far that of the lower mol wt zone; however from the 24 th week one notes a steady increase in the relative magnitude of this second zone until at the end of the gestation period both zones assume near equal importance albeit within a lower total AP activity.

Alkaline phosphatase isoenzyme pattern in human amniotic fluid is dependent on the level of total activity. Implications in cystic fibrosis diagnosis.

Alkaline phosphatase activities have been examined in 500 consecutive human amniotic fluids obtained at diagnostic paracentesis between 14 and 38 wk of gestation. They were found to have a non-Gaussian, positively skewed distribution, independent of the protein concentrations. Residual activities after heat treatment or in presence of phenylalanine and levamisole allow evaluation of the placental, hepatic and intestinal isoenzyme components.

Early and late systemic effects of colchicine on muscle permeability to inorganic phosphate.

A single systemic injection of 75 micrograms colchicine/100 g body weight in the lumbar muscles increases within 6 h the permeability of the extensor digitorum longus muscle to inorganic phosphate. Twenty four hours after the injection the specific activities and isotope uptakes of both inorganic and organic-bound acid-soluble phosphates are markedly increased. By the third day a maximal four-fold increase in rate of inorganic phosphate exchange is reached.