Adaptive regulation of taurine and β-alanine uptake in a human kidney cell line from the proximal tubule

摘要: 1. The underlying mechanisms involved in the adaptive regulation of β-amino acid uptake human proximal tubule were examined by use an immortalized embryonic kidney epithelial cell line (IHKE). 2. results indicated that response to maintain whole-body taurine homeostasis occurs predominantly via changes activity high-affinity transport system alterations capacity and with unaffected half-saturation constant. An was not observed for structurally related β-alanine. 3. Only colchicine, which interferes microtubule organization, capable blocking medium, whereas inhibition protein nucleic synthesis cycloheximide actinomycin D, respectively, did change pattern. 4. Phorbol 12-myristate 13-acetate (PMA), mimicking effects diacylglycerol, induced both β-alanine uptake. By contrast, Ca2+-ionophore A23187, IP3, only stimulated but influx However, effect PMA down-regulation A23187 up-regulation rapid short-lived contrast response, suggesting inositol phospholipid pathway involving diacetylglycerol IP3 is less likely be linked directly regulation, rather plays a role short-term regulation.