Premium
Vasopressin rapidly stimulates NA entry and NA‐K pump activity in quiescent cultures of mouse 3T3 cells
Author(s) -
Mendoza Stanley A.,
Wigglesworth Noel M.,
Rozengurt Enrique
Publication year - 1980
Publication title -
journal of cellular physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.529
H-Index - 174
eISSN - 1097-4652
pISSN - 0021-9541
DOI - 10.1002/jcp.1041050117
Subject(s) - vasopressin , cycloheximide , ouabain , stimulation , efflux , intracellular , medicine , endocrinology , chemistry , oxytocin , hormone , 3t3 cells , diaphragm pump , cell culture , biology , sodium , biochemistry , transfection , protein biosynthesis , genetics , materials science , organic chemistry , micropump , nanotechnology
Addition of (Arg) vasopressin to quiescent cultures of Swiss 3T3 cells rapidly stimulates an ouabain‐sensitive 86 Rb uptake. In contrast the hormone has no significant effect on the rate of efflux of this cation from preloaded cells. The stimulation of 86 Rb uptake is cycloheximide‐insensitive, occurs within minutes of hormone addition and results from an increase in the Vmax of the uptake system. Vasopressin stimulates ion uptake in a concentration‐dependent fashion (1‐100 ng/ml); oxytocin also stimulated the Na‐K pump but at significantly higher concentrations. The stimulation of the Na‐K pump by vasopressin is apparently mediated by an increase in Na entry into the cells, since the hormone (1) strikingly shifts the concentration dependence on Na + of the Na‐K pump, (2) increases 22 Na uptake, and (3) increases intracellular Na contents when the efflux of this ion is blocked by ouabain. Since vasopressin is a potent mitogen for Swiss 3T3 cells, the results provide further evidence in support of a possible role of monovalent ion fluxes in signalling the initiation of growth stimulation.