Hi,

Though I have never done these stains before, it appears the calcitonin-gene related peptide (CGRP) is a marker for afferent fibers in the renal area. You could double stain for Tyrosine Hydroxylase and CGRP and distinguish your two fiber types, similar to the approach taken in the attached paper. Those fibers not double positive for TH and CGRP can be assumed to be efferents.

Antibodies can be found here: https://www.biocompare.com/pfu/110447/soids/45900/Antibodies/CGRP

Thanks a lot! CGRP is also one marker i was thinking of, double staining is very good approach i will definitely try!