As far as I know all charges must be balanced as the alternative is not energetically favorable. However, steric factors and protein folding can influence the size and nature of counter anions around the positive charges. It is possible for the receptor to be folded such that the side chain of a lysine residue in one part of the molecule might come into close proximity to the side chain of a glutamic acid residue on the receptor. Otherwise, small molecules or ligand molecules in the cytosol may act to neutralize charges that appear on residue side chains. Residue side chains may have ionization constants (pks) such that the pH of the cytosolic environment will be important.