Does prostaglandin E1 therapy modify the intracavernous musculature?

Abstract

Purpose: Intracavernous injection of prostaglandin E1 in patients with erectile dysfunction has become widespread. However, to our knowledge long-term side effects on the penile smooth muscles in man have not been documented. We evaluated the histological changes of intracavernous smooth muscle after long-term treatment with prostaglandin E1.

Materials and methods: A total of 10 patients with a mean age of 56.5 years (range 46 to 69) underwent biopsy of the corpora before (5) and after (10 in both corpora) prostaglandin E1 treatment. Between 150 and 250 injections during 3 years were performed, and the dosage varied from 5 to 20 microg. Only 1 patient injected prostaglandin E1 on both sides. Staining with hematoxylin and eosin, and immunohistochemical staining with actin anti-actin of intracavernous smooth muscle and its quantification with computerized image analysis were performed.

Results: No histological difference was observed with classic staining. A reduction was noted in the percentage of intracavernous smooth muscle after treatment in 2 of 5 patients on the side of injection (before 35% and 41%, and after 19% and 30%, respectively) but there was no difference with the other corpus cavernosum. No difference was observed in the percentage of intracavernous smooth muscle between both corpora in the 5 patients with biopsies performed only after treatment.

Conclusions: Prostaglandin E1 does not seem to alter intracavernous structures.