An additional band at 38 kDa was observed that was blocked using the antigenic peptide for SHH. From the size of the product it is hypothesized that this band represents a multimer of the active SHH protein. SHH multimerization has been reported in the literature. The 38-kDa product was unchanged with CN injury (control — 1.070 6 0.04, CN-injured — 1.070 6 0.03, P-value — 0.5, Fig. 5). The localization of SHH and PTCH1 remain unchanged after CN injury by IHC analysis.
Morphological Changes in the Corpora Cavernosa Caused by SHH Inhibition Are Reversible
The corpora cavernosa of adult Sprague Dawley rats were treated with 5E1 SHH inhibitor by Affi-Gel bead injection into the corpora cavernosa. Ten days after injection, the corpora cavernosa had remodeled so that sinusoids were absent in the treated region (Fig. 6). SHH inhibitor was depleted from the beads after 10-14 days. At 4 and 6 wk postinjection, penile morphology was examined and SHH and ACTA1 proteins were assayed by IHC. After 4 wk, sinusoidal morphology was partially reestablished and SHH and ACTA1 were observed in the corpora cavernosa (Fig. 6).
FIG. 6. IHC analysis of ACTA1 staining for smooth muscle in SHH inhibited Sprague Dawley penes 10 days, 4 wk, and 6 wk after injection of SHH inhibitor and PBS, which was used as a control for the bead vehicle. a) The absence of sinusoids and positive staining for smooth muscle are evident during SHH inhibition (1-14 days) in the corpora cavernosa. b) Four weeks after SHH inhibitor injection, the presence of sinusoidal tissue staining positively for ACTA1 was identified. c) Six weeks after SHH inhibitor injection, the morphology of the sinusoidal tissue closely resembled normal corpora cavernosa morphology and was indistinguishable from the PBS-treated control corpora cavernosa (d). Original magnification X 60.