title: Effects of endopeptidase inhibition on the relaxation response of isolated human penile erectile tissue to vasoactive peptides.
abstract: Peptides, such as CNP, CGRP and VIP, are involved in the function of male penile erectile tissue. Tissue levels of said peptides are controlled by the endopeptidase enzymes. Theoretically, the inhibition of the degradation of CNP, CGRP and/or VIP should result in an enhancement in penile smooth muscle relaxation. The effects were investigated of CNP or VIP (0.1 nm-1 μm), without and following pre-exposure of the tissue to a threshold concentration of the endopeptidase inhibitor KC 12615 (10 μm, for 20 min), on the reversion of tension induced by means of electrical field stimulation. Drug effects on the production of cyclic AMP/GMP were also evaluated. Neither KC 12615, CNP and VIP nor the combination of CNP plus KC 12615 or VIP plus KC 12615 increased the response of the tissue to EFS. While no effects were observed of a pre-exposure of the tissue to KC 12615 on the production of cyclic AMP in the presence of VIP, an enhancement was registered in the accumulation of cyclic AMP in the presence of CNP plus KC 12615. Further studies are indicated to investigate whether endopeptidase inhibitors might tend to be more effective in tissues affected by a decreased local production of vasoactive peptides.
authors.affiliation: Department of Urology, Cipto Mangunkusumo Hospital, University of Indonesia School of Medicine, Jakarta, Indonesia.
authors.forename: H E
authors.initials: HE
authors.lastname: Rahardjo
authors.affiliation: Division of Surgery, Department of Urology & Urological Oncology, Hannover Medical School, Hannover, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Reichelt
authors.affiliation: Urological Research Unit, Institute for Biochemical Research & Analysis, Barsinghausen am Deister, Germany.
authors.forename: J E
authors.initials: JE
authors.lastname: Sonnenberg
authors.affiliation: Department of Urology, AGAPLESION St. Markus Hospital, Frankfurt am Main, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Sohn
authors.affiliation: Division of Surgery, Department of Urology & Urological Oncology, Hannover Medical School, Hannover, Germany.
authors.forename: M A
authors.initials: MA
authors.lastname: Kuczyk
authors.affiliation: Division of Surgery, Department of Urology & Urological Oncology, Hannover Medical School, Hannover, Germany.|Urological Research Unit, Institute for Biochemical Research & Analysis, Barsinghausen am Deister, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Ückert
mesh_terms: D000328:Adult; D000242:Cyclic AMP / Q000378:metabolism; D006152:Cyclic GMP / Q000378:metabolism; D004558:Electric Stimulation; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction / Q000187:drug effects*; D009126:Muscle Relaxation / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects* / Q000378:metabolism; D020098:Natriuretic Peptide, C-Type / Q000494:pharmacology*; D010413:Penis / Q000187:drug effects* / Q000378:metabolism; D011480:Protease Inhibitors / Q000494:pharmacology*; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology*; D055815:Young Adult
chemical_list: D011480:Protease Inhibitors; D020098:Natriuretic Peptide, C-Type; D014660:Vasoactive Intestinal Peptide; D000242:Cyclic AMP; D006152:Cyclic GMP
keywords: Endogenous vasoactive peptides; endopeptidase inhibition; human corpus cavernosum