which typically stimulates Sertoli cell proliferation in rodents. The
androgenic effect on rodent Sertoli cells is unlikely to be
mediated directly by Sertoli cell androgen receptor function
since neonatal rodent Sertoli cells apparently do not express the
androgen receptor and specific loss of androgen
receptor expression in Sertoli cells does not influence the size
of the Sertoli cell population . Involvement of peritubular myoid cells has been suggested.
In contrast, the presence
of androgen receptors in Sertoli cells of neonatal pigs
suggests that restrictive androgen-mediated signaling directly
at the Sertoli cell might exist in these young pigs, consistent
with apparent differences in how testicular growth and
differentiation are regulated in pigs and rodents, as supported
by our current and previously published observations.