The effect of PnTx2-6 protein from Phoneutria nigriventer spider toxin on improvement of erectile dysfunction in a rat model of cavernous nerve injury

Urology. 2014 Sep;84(3):730.e9-17. doi: 10.1016/j.urology.2014.05.030.

Abstract

Objective: To explore the therapeutic potential of PnTx2-6 injected 3 times a week for 4 weeks into the intracavernosal tissue in a rat model of bilateral cavernous nerve crush injury (BCNI).

Methods: Eight-week-old male Sprague-Dawley rats were randomly divided into the following 6 groups (n = 5 per group): age-matched control (normal group), BCNI (injury group), post-BCNI phosphate-buffered saline injection (PBS group), post-BCNI Sf9 cell-lysate injection (N/C group), post-BCNI injection of cell lysate from S9 cells infected with wild-type recombinant baculovirus (W/T group), and post-BCNI injection of cell lysate from S9 cells infected with recombinant baculovirus containing PnTx2-6 (PnTx2-6 group). Injections were delivered 3 times a week for 4 weeks. After 4 weeks, intracavernosal pressure-to-mean arterial pressure ratio, smooth muscle and collagen content via the Masson trichrome staining, levels of neural nitric oxide synthase, phosphoendothelial nitric oxide synthase, and cyclic guanosine monophosphate were all measured.

Results: The PnTx2-6 group showed significantly higher intracavernosal pressure-to-mean arterial pressure ratio (P <.05), smooth muscle-to-collagen ratio (P <.01), expression levels of neural nitric oxide synthase, phosphoendothelial nitric oxide synthase (P <.05), and cyclic guanosine monophosphate (P <.05) than all other experimental groups.

Conclusion: We conclude that PnTx2-6 improved erectile function and prevented muscle atrophy in a rat model of BCNI via increased synthesis of nitric oxide and cyclic guanosine monophosphate.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Baculoviridae / metabolism
  • Cyclic GMP / metabolism
  • Disease Models, Animal
  • Endothelium / pathology
  • Erectile Dysfunction / drug therapy*
  • Insecta
  • Male
  • Nerve Crush*
  • Neuropeptides / administration & dosage*
  • Neuropeptides / chemistry*
  • Nitric Oxide / metabolism
  • Nitric Oxide Synthase / metabolism
  • Nitric Oxide Synthase Type I / metabolism
  • Penile Erection / drug effects
  • Penis / drug effects*
  • Rats
  • Rats, Sprague-Dawley
  • Spider Venoms / chemistry*
  • Spiders

Substances

  • Neuropeptides
  • Spider Venoms
  • Tx2 neurotoxin
  • Nitric Oxide
  • Nitric Oxide Synthase
  • Nitric Oxide Synthase Type I
  • Nos1 protein, rat
  • Cyclic GMP