Cytochemical localization of alkaline phosphatase in the spinal cord ependyma of newborn and adult rats.

Loss of BMP2 and BMP4 Signaling in the Dental Epithelium Causes Defective Enamel Maturation and Aberrant Development of Ameloblasts

“…TNAP is a membrane-bound enzyme that may play a role in tissue mineralization through hydrolysis of inorganic pyrophosphate, a known inhibitor of hydroxyapatite crystal development [ 116 , 117 ], and has been suggested to be involved in other cellular functions, including transmembrane movement of ions and metabolites [ 118 , 119 , 120 ] and cell adhesion [ 121 ].…”

Alkaline Phosphatase Activity in the Gonadotropic Cells of Swine Adenohypophysis.

“…Several researchers have described that ALPase activity on the plasma membrane is presumably associated with selective transport of certain metabolites (1,3,26,29). Gonadectomy in swine increases the synthesis and the storage of LH and FSH in which the hypertrophied gonadotropic cells, often large in size, contained a few secretory granules which were scattered within the cytoplasm or located at the periphery (6).…”

“…For the visualization of ALPase activity, the sections were incubated in the lead citrate medium (19) at pH 9.4 for 30 min at 25°C, where sodium -glycerophosphate was used as a substrate. Control sections were incubated in a medium lacking the substrate or were preincubated in a medium containing 2 mM L-cysteine as a inhibitor of ALPase (28,29). After the reaction, the sections were fixed for 1-2 hr in 1 % osmium tetroxide solution adjusted to pH 7.4 with 0.1 M cacodylate buffer, dehydrated with graded ethanol and propylene oxide, and finally embedded in epoxy resin.…”

“…ALPase has been used as a marker enzyme for the luminal plasma membrane of the epithelial cells from small intestine (14, 15) and the ependymal cells from spinal cord (29). Indeed, there is a possibility that ALPase activity plays an important role in the transport of substances across the plasma membrane (3, 26).…”

Fine structural study of Mg-ATPase and alkaline phosphatase activities in the blood-brain barrier of ischemic rats.

“…But when the hypoxic injury was profound, ALPase also showed focal dispersion, which might indicate the permeability change of endothelial cell membrane and partial disruption of the BBB. The ALPase activity may play an important role in the transport of the active substances across the plasma membrane in the BBB, and may be related to a selected transport of certain phosphorylated metabolites across the plasma membrane (12).…”