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New methods of early detection combined with recent advances in surgical techniques have resulted in more patients undergoing radical surgery for treatment of localized carcinoma of the prostate. Over 350 radical prostatectomies have been performed by our group since January 1987. We review the role of radical prostatectomy in the treatment of prostate cancer and our experience with 100 patients undergoing radical retropubic prostatectomy since the advent of nerve-sparing techniques to preserve potency.

Tyramine permeates chromaffin-granule membranes via a reserpine-insensitive mechanism. The rate is unsaturable and increases with pH, indicating permeation of the unprotonated form of the amine. Reserpine-insensitive dopamine uptake is at least 10 times slower, consistent with dopamine's lesser lipophilicity. Dopamine is transported into chromaffin-granule membrane vesicles via a saturable, reserpine-sensitive, proton-linked mechanism. Tyramine inhibits dopamine transport with a Ki of 5-10 microM. Tyramine is not accumulated nearly as well as dopamine because inward transport is opposed by outward permeation. Nevertheless, the velocity of reserpine-sensitive tyramine transport can be deduced from the steady-state level of tyramine accumulation and the rate of permeation. Vmax for tyramine transport is about one-third of the value for dopamine transport. Therefore, two aromatic hydroxyls are not needed for monoamine transport but are required for efficient accumulation and storage.