Journal of Applied Physiology, Vol 65, Issue 2 767-775, Copyright © 1988 by American Physiological Society
Specific reaginic antibody IgG1-induced changes of airway smooth muscle cells
M. Souhrada and J. F. Souhrada
John B. Pierce Foundation Laboratory, New Haven, Connecticut.
It was found that 1) an administration of both immunoglobulin G1 (IgG1) or
immunized serum caused an immediate depolarization and an increase in the
isometric force of airway smooth muscle (ASM) cells, followed by a
sustained hyperpolarization and a return of the tone to the base-line
values; 2) an IgG1 concentration-dependent relationship was found between a
peak depolarization, a peak hyperpolarization, and a peak isometric force;
for these events 50% effective dose (ED50) was found to be 0.17, 0.14, and
0.25 microgram/ml of IgG1, respectively; 3) both electrical and contractile
responses to ovalbumin of ASM cells sensitized with IgG1 were also
dependent on the concentration of IgG1; the ED50 values of this
relationship were 0.27 and 0.25 micrograms/ml of IgG1, respectively; 4)
amiloride (10(-8) to 10(-5) M) pretreatment and a sodium-deficient
environment attenuated sensitized-induced electrical and contractile
changes as well as the response of ASM to ovalbumin (0.1%); and 5)
pretreatment of ASM with diphenhydramine (10(-5) M) or FPL 55712 (10(-6) M)
had no effect on sensitization-induced changes in membrane potential but
attenuated electrical and contractile response of ASM to ovalbumin (0.1%).
