This study was designed to investigate whether fibrosis of the corpus cavrnuoum(CC) induced by repeated intracavernous injection of papaverine HCI was related to pH of the drug. Forty-eight New Zealand White rabbits weighing 2.5kg-3.0kg were
divided
into 4 groups of 12 animals each. Group I received isotonic saline, Group 2;p pH 2,0 papaverine HCI, Group 3; pH 3.0 papaverine HCI and Group 4; pH 4.0 papaverine HCI. The solution (0.1ml isotonic saline or 2mg. papaverine HCI of each pH) was
injected
intracorporeally twice every week for 6 months. Every one month since beginning of the injection, 2 animals of each group were sacrified, the penis was observed with H & E and Masson's trichorome stain microscopically.No sign of fibrosis was
found
in
the CC of the group 1 even after 6months of injection. However, Group 2, 3 and 4 began to show focal of diffuse thin fibrotic changes after 2 months of injection. The fibrotic changes progressed more and more in accordance with the frequency of
papaverine HCI injection. After 4 months of injection. Group 2 showed diffuse thick fibrosis whereas Group 3 and 4 shoed diffuse thin or focal thick fibrosis. In conclusion, intracavernous papaverine itself seems to play a main role to induce
fibrosis
of CC. However, the acidity of the papaverine HCI also might be responsible to development of the fibrosis when injected repeatedly for a long period.
|