Korean J Physiol Pharmacol.  2014 Dec;18(6):489-495. 10.4196/kjpp.2014.18.6.489.

Suppression of Peripheral Sympathetic Activity Underlies Protease-Activated Receptor 2-Mediated Hypotension

• Kim YH
• Ahn DS
• Joeng JH
• Chung S

• KMID: 2285551
• DOI: http://doi.org/10.4196/kjpp.2014.18.6.489

Abstract

Protease-activated receptor (PAR)-2 is expressed in endothelial cells and vascular smooth muscle cells. It plays a crucial role in regulating blood pressure via the modulation of peripheral vascular tone. Although some reports have suggested involvement of a neurogenic mechanism in PAR-2-induced hypotension, the accurate mechanism remains to be elucidated. To examine this possibility, we investigated the effect of PAR-2 activation on smooth muscle contraction evoked by electrical field stimulation (EFS) in the superior mesenteric artery. In the present study, PAR-2 agonists suppressed neurogenic contractions evoked by EFS in endothelium-denuded superior mesenteric arterial strips but did not affect contraction elicited by the external application of noradrenaline (NA). However, thrombin, a potent PAR-1 agonist, had no effect on EFS-evoked contraction. Additionally, omega-conotoxin GVIA (CgTx), a selective N-type Ca2+ channel (I(Ca-N)) blocker, significantly inhibited EFS-evoked contraction, and this blockade almost completely occluded the suppression of EFS-evoked contraction by PAR-2 agonists. Finally, PAR-2 agonists suppressed the EFS-evoked overflow of NA in endothelium-denuded rat superior mesenteric arterial strips and this suppression was nearly completely occluded by omega-CgTx. These results suggest that activation of PAR-2 may suppress peripheral sympathetic outflow by modulating activity of I(Ca-N) which are located in peripheral sympathetic nerve terminals, which results in PAR-2-induced hypotension.

Keyword

Hypotension; Mesenteric artery; N-type Ca2+ channel; Peripheral sympathetic output; Protease-activated receptor 2

MeSH Terms

Animals
Blood Pressure
Endothelial Cells
Hypotension*
Mesenteric Arteries
Mesenteric Artery, Superior
Muscle, Smooth
Muscle, Smooth, Vascular
Norepinephrine
omega-Conotoxin GVIA
Rats
Receptor, PAR-2
Thrombin
Norepinephrine
Receptor, PAR-2
Thrombin
omega-Conotoxin GVIA

Figure

• 

  Fig. 1 Effect of PAR-2 agonists on EFS-induced contraction in endothelium-denuded rat superior mesenteric arterial strips. (A) a representative trace of inhibition of EFS-induced contraction by application of 30 nM trypsin (left) or 30 nM BT (right) (B) a representative trace of inhibition of EFS-induced contraction by application of 100µM SL-NH2 (left) or LR-NH2 (right) (C) summarized time course of trypsin (0.17±0.04 g for control, 0.10±0.03 g for trypsin, n=6, p<0.05) or BT (0.9±3.5% inhibition; 0.10±0.02 g for control, 0.10±0.03 g for BT, n=6, p>0.05) effects on EFS-induced contraction. (D) summarized time course of SL-NH2 (0.11±0.04 g for control; 0.07±0.01 g for SL-NH2, n=6, p<0.05) or LR-NH2 (2.6±3.1% inhibition; 0.6±0.1 g for control; 0.6±0.1 g for LR-NH2, n=6, p>0.05) effects on EFS-induced contraction. (E) right, Concentration-response curves for trypsin. Left Concentration-response curves for SL-NH2.

• 

  Fig. 2 Effect of NA and of NA plus PAR-2 agonists on the response to EFS-induced contraction in endothelium-denuded superior mesenteric arterial strip. (A) A representative trace of trypsin (30 nM) effect on the contraction evoked by externally applied NA (1µM). (B) Summary of trypsin effect on NA-evoked vasoconstriction (0.55±0.13 g for NA, 0.53±0.13 g for NA+trypsin, n=5, p>0.05). (C) A representative trace of SL-NH2 (100µM) effect on the contraction evoked by externally applied NA (1µM). (D) Summary of SL-NH2 effect on NA-evoked vasoconstriction (0.7±0.05 g for NA; 0.66±0.03 g for NA+SL-NH2, n=5, p>0.05).

• 

  Fig. 3 Effects of ω-CgTx on inhibitory effect of PAR-2 agonists on EFS-induced contraction in rat endothelium-denuded superior mesenteric arterial strips. (A) A representative trace of the effects induced by consecutive application of ω-CgTx (1µM) and trypsin (30 nM) on EFS-induced contraction. (B) Summary of ω-CgTx effect on trypsin-induced inhibition of EFS-induced contraction (ω-CgTx; 65.0±2.9%, ω-CgTx+trypsin; 62.2±3.2%, p>0.05, n=5). (C) A representative trace of the effects induced by consecutive application of ω-CgTx (1µM) and SL-NH2 (100µM) on EFS-induced contraction. (D) Summary of ω-CgTx effect on SL-NH2-induced inhibition of EFS-induced contraction (ω-CgTx; 66.4±2.3%, ω-CgTx +SL-NH2; 60.6±2.3%, p>0.05, n=5).

• 

  Fig. 4 Effect of PAR-2 agonist on EFS-evoked overflow of NA in endothelium-denuded rat superior mesenteric arterial strips. (A) summary of the effects of trypsin (7.1±0.2 pq/ml for control, 6.0±0.3 pq/ml for trypsin, n=4, p<0.001), SL-NH2 (7.0±0.3 pq/ml for control; 6.1±0.2 pq/ml for SL-NH2, n=4, p<0.001), BT (6.2±0.2 pq/ml for control, 6.3±0.2 pq/ml for BT, n=4, P>0.05), or LR-NH2 (6.7±0.2 pq/ml for control; 6.8±0.2 pq/ml for LR-NH2, n=4, p>0.05) on the EFS-evoked overflow of NA in rat superior mesenteric arterial strips. (B) summary of ω-CgTx effect on trypsin or SL-NH2-induced inhibition of EFS-evoked overflow of NA in rat superior mesenteric arterial strips (ω-CgTx; 17.6±0.5%, ω-CgTx+trypsin; 17.7±1.1%, p>0.05, n=4), (ω-CgTx; 16.1±0.6%, ω-CgTx+SL-NH2; 15.8±1.2%, p>0.05, n=4).

• 

  Fig. 5 PAR-2 agonists inhibited ICa in rat SCG neurons (A) Left, a representative trace of ICa in the presence (●) and absence (○) of 30 nM typsin. Right, a representative trace of ICa in the presence (●) and absence (○) of 30 nM BT. (B) Left, a representative traces of ICa in the presence (●) and absence (○) of 100µM SL-NH2. Right, a representative trace of ICa in the presence (●) and absence (○) of 100µM LR-NH2. (C) left, a summary of ICa inhibition by trypsin (815.5±104.9 pA for control; 428.0±54.1 pA for trypsin, n=5) and BT (906.6±115.7 pA for control, 863.1±125.6 pA for BT, n=5, p>0.05). Right a summary of ICa inhibition by SL-NH2 (902.5±111.6 pA for control, 506.1±58.8 pA for SL-NH2, n=5) or LR-NH2 (786.8±67.1 pA for control, 727.1±71.2 pA for LR-NH2, n=5, p>0.01).

Reference

1. Kawabata A, Kuroda R, Hollenberg MD. Physiology of protease-activated receptors (PARs): involvement of PARs in digestive functions. Nihon Yakurigaku Zasshi. 1999; 114(Suppl 1):173P–179P.

2. al-Ani B, Saifeddine M, Hollenberg MD. Detection of functional receptors for the proteinase-activated-receptor-2-activating polypeptide, SLIGRL-NH2, in rat vascular and gastric smooth muscle. Can J Physiol Pharmacol. 1995; 73:1203–1207. PMID: 8564891.

3. Hollenberg MD, Saifeddine M, al-Ani B. Proteinase-activated receptor-2 in rat aorta: structural requirements for agonist activity of receptor-activating peptides. Mol Pharmacol. 1996; 49:229–233. PMID: 8632754.

4. Magazine HI, King JM, Srivastava KD. Protease activated receptors modulate aortic vascular tone. Int J Cardiol. 1996; 53(Suppl):S75–S80. PMID: 8793596.

5. Saifeddine M, al-Ani B, Cheng CH, Wang L, Hollenberg MD. Rat proteinase-activated receptor-2 (PAR-2): cDNA sequence and activity of receptor-derived peptides in gastric and vascular tissue. Br J Pharmacol. 1996; 118:521–530. PMID: 8762073.

6. Emilsson K, Wahlestedt C, Sun MK, Nystedt S, Owman C, Sundelin J. Vascular effects of proteinase-activated receptor 2 agonist peptide. J Vasc Res. 1997; 34:267–272. PMID: 9256086.

7. Cicala C, Pinto A, Bucci M, Sorrentino R, Walker B, Harriot P, Cruchley A, Kapas S, Howells GL, Cirino G. Protease-activated receptor-2 involvement in hypotension in normal and endotoxemic rats in vivo. Circulation. 1999; 99:2590–2597. PMID: 10330393.

8. Cicala C, Morello S, Santagada V, Caliendo G, Sorrentino L, Cirino G. Pharmacological dissection of vascular effects caused by activation of protease-activated receptors 1 and 2 in anesthetized rats. FASEB J. 2001; 15:1433–1435. PMID: 11387248.

9. Cheung WM, Andrade-Gordon P, Derian CK, Damiano BP. Receptor-activating peptides distinguish thrombin receptor (PAR-1) and protease activated receptor 2 (PAR-2) mediated hemodynamic responses in vivo. Can J Physiol Pharmacol. 1998; 76:16–25. PMID: 9564545.

10. Damiano BP, Cheung WM, Santulli RJ, Fung-Leung WP, Ngo K, Ye RD, Darrow AL, Derian CK, de Garavilla L, Andrade-Gordon P. Cardiovascular responses mediated by proteaseactivated receptor-2 (PAR-2) and thrombin receptor (PAR-1) are distinguished in mice deficient in PAR-2 or PAR-1. J Pharmacol Exp Ther. 1999; 288:671–678. PMID: 9918574.

11. Kawabata A, Nakaya Y, Kuroda R, Wakisaka M, Masuko T, Nishikawa H, Kawai K. Involvement of EDHF in the hypotension and increased gastric mucosal blood flow caused by PAR-2 activation in rats. Br J Pharmacol. 2003; 140:247–254. PMID: 12970102.

12. Lee CC, Lee YY, Chang CK, Lin MT. Selective inhibition of inducible nitric oxide synthase attenuates renal ischemia and damage in experimental heatstroke. J Pharmacol Sci. 2005; 99:68–76. PMID: 16127242.

13. Emilsson V, Arch JR, de Groot RP, Lister CA, Cawthorne MA. Leptin treatment increases suppressors of cytokine signaling in central and peripheral tissues. FEBS Lett. 1999; 455:170–174. PMID: 10428495.

14. Molderings GJ, Likungu J, Göthert M. N-Type calcium channels control sympathetic neurotransmission in human heart atrium. Circulation. 2000; 101:403–407. PMID: 10653832.

15. Shimosawa T, Takano K, Ando K, Fujita T. Magnesium inhibits norepinephrine release by blocking N-type calcium channels at peripheral sympathetic nerve endings. Hypertension. 2004; 44:897–902. PMID: 15477382.

16. Ryu SK, Ahn DS, Cho YE, Choi SK, Kim YH, Morgan KG, Lee YH. Augmented sphingosylphosphorylcholine-induced Ca²⁺-sensitization of mesenteric artery contraction in spontaneously hypertensive rat. Naunyn Schmiedebergs Arch Pharmacol. 2006; 373:30–36. PMID: 16521007.

17. Zygmunt PM, Högestätt ED. Calcium channels at the adrenergic neuroeffector junction in the rabbit ear artery. Naunyn Schmiedebergs Arch Pharmacol. 1993; 347:617–623. PMID: 8395661.

18. Ralevic V, Karoon P, Burnstock G. Long-term sensory denervation by neonatal capsaicin treatment augments sympathetic neurotransmission in rat mesenteric arteries by increasing levels of norepinephrine and selectively enhancing postjunctional actions. J Pharmacol Exp Ther. 1995; 274:64–71. PMID: 7616449.

19. Kim T, La J, Lee J, Yang I. Effects of nitric oxide on slow waves and spontaneous contraction of guinea pig gastric antral circular muscle. J Pharmacol Sci. 2003; 92:337–347. PMID: 12939518.

20. Asano M, Nomura N, Sasaki S, Mishima A. Surgical repair of tetralogy of Fallot with large conus artery. Pediatr Cardiol. 2003; 24:601–603. PMID: 12717594.

21. Nystedt S, Emilsson K, Wahlestedt C, Sundelin J. Molecular cloning of a potential proteinase activated receptor. Proc Natl Acad Sci U S A. 1994; 91:9208–9212. PMID: 7937743.

22. Lamont C, Vainorius E, Wier WG. Purinergic and adrenergic Ca²⁺ transients during neurogenic contractions of rat mesenteric small arteries. J Physiol. 2003; 549:801–808. PMID: 12740429.

23. Sadraei H, Large BJ, Hughes IE. Mechanisms involved in electrically-induced responses of rat seminal vesicles. J Pharm Pharmacol. 1995; 47:665–668. PMID: 8583369.

24. Tanaka Y, Mochizuki Y, Tanaka H, Shigenobu K. Significant role of neuronal non-N-type calcium channels in the sympathetic neurogenic contraction of rat mesenteric artery. Br J Pharmacol. 1999; 128:1602–1608. PMID: 10602342.

25. Recio P, Orensanz LM, Martnez MP, Navarro-Dorado J, Bustamante S, García-Sacristán A, Prieto D, Hernández M. Noradrenergic vasoconstriction of pig prostatic small arteries. Naunyn Schmiedebergs Arch Pharmacol. 2008; 376:397–406. PMID: 18172615.

26. Whorlow SL, Angus JA, Wright CE. Selectivity of omegaconotoxin GVIA for n-type calcium channels in rat isolated small mesenteric arteries. Clin Exp Pharmacol Physiol. 1996; 23:16–21. PMID: 8713491.

27. Chien EK, Sweet L, Phillippe M, Marietti S, Kim TT, Wolff DA, Thomas L, Bieber E. Protease-activated receptor isoform expression in pregnant and nonpregnant rat myometrial tissue. J Soc Gynecol Investig. 2003; 10:460–468.

28. Hwa JJ, Ghibaudi L, Williams P, Chintala M, Zhang R, Chatterjee M, Sybertz E. Evidence for the presence of a proteinase-activated receptor distinct from the thrombin receptor in vascular endothelial cells. Circ Res. 1996; 78:581–588. PMID: 8635215.

29. Hamilton JR, Nguyen PB, Cocks TM. Atypical protease-activated receptor mediates endothelium-dependent relaxation of human coronary arteries. Circ Res. 1998; 82:1306–1311. PMID: 9648727.

30. Roy SS, Saifeddine M, Loutzenhiser R, Triggle CR, Hollenberg MD. Dual endothelium-dependent vascular activities of proteinase-activated receptor-2-activating peptides: evidence for receptor heterogeneity. Br J Pharmacol. 1998; 123:1434–1440. PMID: 9579740.

31. Sobey CG, Moffatt JD, Cocks TM. Evidence for selective effects of chronic hypertension on cerebral artery vasodilatation to protease-activated receptor-2 activation. Stroke. 1999; 30:1933–1940. discussion 1941. PMID: 10471447.

32. McGuire JJ. Proteinase-activated Receptor 2 (PAR2): a challenging new target for treatment of vascular diseases. Curr Pharm Des. 2004; 10:2769–2778. PMID: 15320742.

33. Camerer E, Cornelissen I, Kataoka H, Duong DN, Zheng YW, Coughlin SR. Roles of protease-activated receptors in a mouse model of endotoxemia. Blood. 2006; 107:3912–3921. PMID: 16434493.

34. McGuire JJ, Van Vliet BN, Halfyard SJ. Blood pressures, heart rate and locomotor activity during salt loading and angiotensin II infusion in protease-activated receptor 2 (PAR2) knockout mice. BMC Physiol. 2008; 8:20. PMID: 18939990.

35. Hille B. Modulation of ion-channel function by G-protein-coupled receptors. Trends Neurosci. 1994; 17:531–536. PMID: 7532338.