PHYSICAL REVIEW D, vol.54, no.7, pp.4561-4565, 1996 (SCI-Expanded)
We apply the three conditions of the Glashow-Weinberg extension of the GIM mechanism for the absence of order G(F) and alpha G(F) flavor-changing neutral currents to the SU(3)(L) x U(1)(x) models of electroweak interactions. We find that these currents can be suppressed without fine-tuning of the parameters, and we obtain lower and upper bounds on the mass of the second neutral gauge boson.