title: Chronic oral administration of the arginase inhibitor 2(S)-amino-6-boronohexanoic acid (ABH) improves erectile function in aged rats.
abstract: Arginase expression and activity have been noted to be heightened in  conditions associated with erectile dysfunction, including aging. Previously,  arginase inhibition by chronic administration of the arginase inhibitor  2-(S)-amino-6-boronohexanoic acid (ABH) has been shown to improve  endothelial dysfunction in aged rats. The objective of this study was to  assess whether chronic oral ABH administration affects cavernosal erectile  function. Rats were divided into 4 groups: young control, young treated with  arginase inhibitor, aged control, and aged treated with arginase inhibitor.  Arginase activity was measured and presented as a proportion of young  untreated rats. In vivo erectile responses to cavernous nerve stimulation were  measured in all cohorts. The cavernous nerve was stimulated with a graded  electrical stimulus, and the intracavernosal/mean arterial pressure ratios and  total intracavernosal pressure were recorded. Arginase activity was elevated  in the aged rats compared with young controls; however, arginase activity was  significantly decreased in aged rats treated with ABH. With the addition of  ABH, erectile responses improved in the aged rats (P < .05). Oral  inhibition of arginase with ABH results in improved erectile function in aged  rats, resulting in erectile hemodynamics similar to young rats. This  represents the first documentation of systemic arginase inhibition positively  affecting corporal cavernosal function.
authors.affiliation: Department of Urology, The James Buchanan Brady Urological Institute, Johns Hopkins MedicalInstitutions, Baltimore, Maryland, USA. rsegal3@jhmi.edu
authors.forename: Robert
authors.initials: R
authors.lastname: Segal
authors.forename: Johanna L
authors.initials: JL
authors.lastname: Hannan
authors.forename: Xiaopu
authors.initials: X
authors.lastname: Liu
authors.forename: Omer
authors.initials: O
authors.lastname: Kutlu
authors.forename: Arthur L
authors.initials: AL
authors.lastname: Burnett
authors.forename: Hunter C
authors.initials: HC
authors.lastname: Champion
authors.forename: Jae Hyung
authors.initials: JH
authors.lastname: Kim
authors.forename: Jochen
authors.initials: J
authors.lastname: Steppan
authors.forename: Dan E
authors.initials: DE
authors.lastname: Berkowitz
authors.forename: Trinity J
authors.initials: TJ
authors.lastname: Bivalacqua
mesh_terms: D000284:Administration, Oral; D000375:Aging / Q000502:physiology; D000614:Aminocaproates / Q000008:administration & dosage / Q000627:therapeutic use*; D000818:Animals; D001119:Arginase; D001896:Boron Compounds / Q000008:administration & dosage / Q000627:therapeutic use*; D004558:Electric Stimulation; D004791:Enzyme Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D007172:Erectile Dysfunction / Q000188:drug therapy*; D008297:Male; D010410:Penile Erection / Q000502:physiology*; D010413:Penis / Q000201:enzymology / Q000294:innervation; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: C121228:2-amino-6-boronohexanoic acid; D000614:Aminocaproates; D001896:Boron Compounds; D004791:Enzyme Inhibitors; D001119:Arginase