In a spin-polarized electron gas, the effect of the exchange ͑x͒ and correlation ͑c͒ interactions can be incorporated into the dynamic response functions through spin-dependent local-field corrections G␴ x,c(␻,qជ). We obtain the zero-frequency and long-wavelength limits of G␴ x,c(␻,qជ) by analyzing the connection between the macroscopic response function and the thermodynamic parameters of the system.