Identification of a down-regulated mRNA transcript in corpus cavernosum from diabetic patients with erectile dysfunction.

Fifty per cent of men with diabetes have erectile dysfunction. Previous studies demonstrated that cultured smooth muscle cells from corpus cavernosum display significantly altered K+ channel function, PGE-induced cAMP accumulation, and endothelin-1 induced Ca2+ mobilization that are consistent with the pathophysiology of erectile dysfunction. Since defects in signal transduction frequently lead to altered gene expression, we examined differences in gene expression in corporal tissue excised from three diabetic patients with erectile dysfunction function and one patient with neurogenic erectile dysfunction. Using differential display, we identify a transcript expressed in tissue derived from the patient with impotence secondary to a radical prostectomy, but which was greatly reduced or absent in corporal tissue from all three diabetic patients examined. DNA sequence analysis indicates that this transcript has no significant homology to sequences presently deposited in the GenBank database. This suggests that altered gene expression may play a significant part in the etiology of erectile dysfunction.