Altered contractile response of penis under hypoxia with metabolic acidosis

D. G. Moon, D. S. Lee, J. J. Kim

    Research output: Contribution to journalArticlepeer-review

    30 Citations (Scopus)

    Abstract

    Previous studies concerning ischemic priapism revealed that hypoxia alters the erectile and contractile responses of penis. But the effects of accompanying acidosis on those responses have not been fully evaluated or understood yet. We performed this study to elucidate the role of acidosis on the trabecular smooth muscle contractility like in ischemic priapism. Under the general anesthesia, 55 mature male cats were conditioned to systemic metabolic acidosis by hypoventilation by animal ventilator. The changes of intracavernous pressure (ICP) to erectogenic agents (acetylcholine, L-arginine, prostaglandin E1: PGE1), erectolytic agents (epinephrine, thromboxane A2; TXA2), K channel-related drugs (pinacidil, 4-aminopyridine, tetraethylammonium; TEA, glibenclamide) and calcium ionophore were monitored at Set 1 (PO2 > 60 mmHg, pH > 7.25), Set 2 (PO2 < 30 mmHg, 7.25 > pH > 7.0), Set 3 (PO2 < 30 mmHg, pH < 7.0), and Set 4 (PO2 > 60 mmHg, pH < 7.0) in vivo. At Set 1 and Set 2, epinephrine, TXA2, and ionomycin decreased the ICP by acetylcholine or PGE2 (n = 9, P < 0.01). The decrease of ICP was in order of epinephrine, TXA2 and ionomycin. Acidosis reduced the increase of ICP to acetylcholine or PGE1 (n = 8, P < 0.01), TXA2 or ionomycin did not affect ICP under severe acidosis but epinephrine decreased ICP even under severe acidosis (n = 7, P < 0.05). Pretreatment of potassium channel blockers did not suppress the increase of ICP by erectogenic agents under acidosis (n = 6, P < 0.05). Pinacidil did not affect ICP under acidosis (n = 6, P < 0.01). These results suggest that acidosis impairs the contractile response of cavernous smooth muscle to erectolytic agents. It may be the results of the interference by [H+] with the intra and extracellular mechanisms that regulate the homeostasis of [Ca2]. Conclusively, besides hypoxia, acidosis is another limiting factor of trabecular smooth muscle contractility like in ischemic priapism.

    Original languageEnglish
    Pages (from-to)265-271
    Number of pages7
    JournalInternational Journal of Impotence Research
    Volume11
    Issue number5
    DOIs
    Publication statusPublished - 1999 Oct

    Keywords

    • Acidosis
    • Priapism
    • Trabecular smooth muscle contractility

    ASJC Scopus subject areas

    • Urology

    Fingerprint

    Dive into the research topics of 'Altered contractile response of penis under hypoxia with metabolic acidosis'. Together they form a unique fingerprint.

    Cite this