Korean J Urol.  2013 May;54(5):333-338. 10.4111/kju.2013.54.5.333.

Relaxing Effect of Acetylcholine on Phenylephrine-Induced Contraction of Isolated Rabbit Prostate Strips Is Mediated by Neuronal Nitric Oxide Synthase

• Nguyen HB
• Lee SY
• Park SH
• Lee MY
• Chang IH
• Myung SC

• KMID: 2061516
• DOI: http://doi.org/10.4111/kju.2013.54.5.333

Abstract

PURPOSE
The location of acetylcholinesterase-containing nerve fibers suggests a role for acetylcholine in both contractility and secretion in the prostate gland. The colocalization of nitrergic nerves with cholinergic nerves, and the cotransmission of nitric oxide with acetylcholine in cholinergic nerves, has been demonstrated in the prostate glands of various species. Thus, we investigated the effects of acetylcholine on phenylephrine-induced contraction and the correlation between cholinergic transmission and nitric oxide synthase by using isolated prostate strips of rabbits.
MATERIALS AND METHODS
Isolated prostate strips were contracted with phenylephrine and then treated with cumulative concentrations of acetylcholine. Changes in acetylcholine-induced relaxation after preincubation with NG-nitroarginine methyl ester, 7-nitroindazole, and aminoguanidine were measured. The effects of selective muscarinic receptor antagonists were also evaluated.
RESULTS
In the longitudinal phenylephrine-contracted strip, the cumulative application of acetylcholine (10(-9) to 10(-4) M) elicited a concentration-dependent relaxation effect. Acetylcholine-induced relaxation was inhibited not only by nitric oxide synthase inhibitors (10 microM L-NAME or 10 microM 7-nitroindazole) but also by 10 microM atropine and some selective muscarinic receptor antagonists (10(-6) M 11-([2-[(diethylamino)methyl]-1-piperdinyl]acetyl)-5,11-dihydro-6H-pyrido[2,3-b][1,4]benzodiazepine-6-one and 10(-6) M 4-diphenylacetoxy-N-methyl-piperidine). In contrast, relaxation was significantly increased by pretreatment of the strips with 10 mM L-arginine.
CONCLUSIONS
Acetylcholine relaxed phenylephrine-induced contractions of isolated rabbit prostate strips. This relaxation may be mediated via both cholinergic and constitutive nitric oxide synthase with both the M2 and M3 receptors possibly playing key roles.

Keyword

Acetylcholine; Muscarinic M2 receptor; Muscarinic M3 receptor; Nitric oxide synthase type I; Prostate

MeSH Terms

Acetylcholine
Atropine
Contracts
Guanidines
Indazoles
Nerve Fibers
Neurons
NG-Nitroarginine Methyl Ester
Nitrergic Neurons
Nitric Oxide
Nitric Oxide Synthase
Nitric Oxide Synthase Type I
Phenylephrine
Prostate
Receptor, Muscarinic M2
Receptor, Muscarinic M3
Receptors, Muscarinic
Relaxation
Acetylcholine
Atropine
Guanidines
Indazoles
NG-Nitroarginine Methyl Ester
Nitric Oxide
Nitric Oxide Synthase
Nitric Oxide Synthase Type I
Phenylephrine
Receptor, Muscarinic M2
Receptor, Muscarinic M3
Receptors, Muscarinic

Figure

• 

  FIG. 1 Schematic representation of the strips from rabbit prostate. Only 2 longitudinal strips (strip 1 and 2) of the adenomatous tissue surrounding the urethra were used in each experiment.

• 

  FIG. 2 (A) Original trace showing the dose-dependent relaxation responses of a phenylephrine (PE)-contracted strip to acetylcholine (ACh). (B) Relaxation effect of ACh on PE-contracted prostate strips (n=8, Student's t-test). W/O, washout.

• 

  FIG. 3 (A) Effect of hexamethonium and atropine on acetylcholine-induced relaxation in phenylephrine-contracted strips (n=12, repeated-measures analysis of variance, a:p<0.05). (B) Comparative effects of 11-([2-[(diethylamino)methyl]-1-piperdinyl]acetyl)-5,11-dihydro-6H-pyrido[2,3-b][1,4]benzodiazepine-6-one (10-6 M) and 4-diphenylacetoxy-N-methyl-piperidine (10-6 M), selective M2 and M3 muscarinic receptor antagonists, respectively, on acetylcholine-induced relaxation in phenylephrine-contracted preparations (n=12, repeated-measures analysis of variance, a:p<0.05). ACh, acetylcholine.

• 

  FIG. 4 Effect of NG-nitroarginine methyl ester (L-NAME) and L-arginine on acetylcholine-induced relaxation in phenylephrine-contracted strips (n=12, repeated-measures analysis of variance, a,b:p<0.05). ACh, acetylcholine.

• 

  FIG. 5 Effect of 7-nitroindazole and aminoguanidine on acetylcholine-induced relaxation in phenylephrine-contracted strips (n=12, repeated-measures analysis of variance, a:p<0.05). ACh, acetylcholine.

Reference

1. Pennefather JN, Lau WA, Mitchelson F, Ventura S. The autonomic and sensory innervation of the smooth muscle of the prostate gland: a review of pharmacological and histological studies. J Auton Pharmacol. 2000. 20:193–206.

2. McVary KT, McKenna KE, Lee C. Prostate innervation. Prostate Suppl. 1998. 8:2–13.

3. Wang JM, McKenna KE, Lee C. Determination of prostatic secretion in rats: effect of neurotransmitters and testosterone. Prostate. 1991. 18:289–301.

4. Takeda M, Tang R, Shapiro E, Burnett AL, Lepor H. Effects of nitric oxide on human and canine prostates. Urology. 1995. 45:440–446.

5. Hedlund P, Larsson B, Alm P, Andersson KE. Nitric oxide synthase-containing nerves and ganglia in the dog prostate: a comparison with other transmitters. Histochem J. 1996. 28:635–642.

6. Ventura S, Pennefather J, Mitchelson F. Cholinergic innervation and function in the prostate gland. Pharmacol Ther. 2002. 94:93–112.

7. Andersson KE, Persson K. Nitric oxide synthase and nitric oxide-mediated effects in lower urinary tract smooth muscles. World J Urol. 1994. 12:274–280.

8. Mumtaz FH, Khan MA, Thompson CS, Morgan RJ, Mikhailidis DP. Nitric oxide in the lower urinary tract: physiological and pathological implications. BJU Int. 2000. 85:567–578.

9. Dixon JS, Jen PY, Gosling JA. The distribution of vesicular acetylcholine transporter in the human male genitourinary organs and its co-localization with neuropeptide Y and nitric oxide synthase. Neurourol Urodyn. 2000. 19:185–194.

10. Andersson KE, Arner A. Urinary bladder contraction and relaxation: physiology and pathophysiology. Physiol Rev. 2004. 84:935–986.

11. Seki N, Nishiye E, Itoh T, Suzuki H, Kuriyama H. Electrical and mechanical properties of the capsular smooth muscles of the rabbit prostate in relation to the actions of the alpha 1-adrenoceptor blocker, YM-12617. Br J Pharmacol. 1988. 93:702–714.

12. Fernandez JL, Rivera L, Lopez PG, Recio P, Vela-Navarrete R, García-Sacristán A. Characterization of the muscarinic receptor mediating contraction of the dog prostate. J Auton Pharmacol. 1998. 18:205–211.

13. Arver S, Sjostrand NO. Functions of adrenergic and cholinergic nerves in canine effectors of seminal emission. Acta Physiol Scand. 1982. 115:67–77.

14. Park JH, Park KS, Cha SK, Lee KI, Kim MJ, Park JY, et al. Characterization of acetylcholine-induced currents in male rat pelvic ganglion neurons. Korean J Physiol Pharmacol. 2004. 8:219–225.

15. Smith ER, Miller TB, Wilson MM, Appel MC. Effects of vasoactive intestinal peptide on canine prostatic contraction and secretion. Am J Physiol. 1984. 247(4 Pt 2):R701–R708.

16. Lepor H, Gup DI, Baumann M, Shapiro E. Laboratory assessment of terazosin and alpha-1 blockade in prostatic hyperplasia. Urology. 1988. 32:6 Suppl. 21–26.

17. Caine M, Raz S, Zeigler M. Adrenergic and cholinergic receptors in the human prostate, prostatic capsule and bladder neck. Br J Urol. 1975. 47:193–202.

18. Hedlund H, Andersson KE, Larsson B. Alpha-adrenoceptors and muscarinic receptors in the isolated human prostate. J Urol. 1985. 134:1291–1298.

19. Pontari MA, Luthin GR, Braverman AS, Ruggieri MR. Characterization of muscarinic cholinergic receptor subtypes in rat prostate. J Recept Signal Transduct Res. 1998. 18:151–166.

20. Shikata H, Utsumi N, Hiramatsu M, Minami N, Nemoto N, Shikata T. Immunohistochemical localization of nerve growth factor and epidermal growth factor in guinea pig prostate gland. Histochemistry. 1984. 80:411–413.

21. Lepor H, Kuhar MJ. Characterization of muscarinic cholinergic receptor binding in the vas deferens, bladder, prostate and penis of the rabbit. J Urol. 1984. 132:392–396.

22. Burnett AL, Maguire MP, Chamness SL, Ricker DD, Takeda M, Lepor H, et al. Characterization and localization of nitric oxide synthase in the human prostate. Urology. 1995. 45:435–439.

23. Najbar-Kaszkiel AT, Di Iulio JL, Li CG, Rand MJ. Characterisation of excitatory and inhibitory transmitter systems in prostate glands of rats, guinea pigs, rabbits and pigs. Eur J Pharmacol. 1997. 337:251–258.

24. Hedlund P, Ekstrom P, Larsson B, Alm P, Andersson KE. Heme oxygenase and NO-synthase in the human prostate: relation to adrenergic, cholinergic and peptide-containing nerves. J Auton Nerv Syst. 1997. 63:115–126.