Equivalent circuit of a membrane

hi guys!
Well I combined some pictures of the book "Introduction to biomedical engineering" by "JOSEPH BRONZINO, SERIES EDITOR" (second edition) to ask some questions.
In figure 11.14, ignoring Na-K pump in shaded box still satisfies the KCL but I don't understand why does the book keep saying in the two following figures that the Na-K pump (the two current sources) can be neglected?
Does it still satisfies the KCL?
Any of you guys know about "Goldman" equation or "Hudgkin-Huxley" model of a membrane so he/she can explain this to me?

Thanks in advance...