Modulation of iris sphincter and ciliary muscles by urocortin 2

Title:

Modulation of iris sphincter and ciliary muscles by urocortin 2

Creator:

Tavares-Silva, M., Ferreira, D., Cardoso, S., Raimundo, A. R., Barbosa-Breda, J., Leite-Moreira, A., and Rocha-Sousa, A.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:130c6bbc-1422-4e99-a264-38fb029ad82c
uuid:130c6bbc-1422-4e99-a264-38fb029ad82c
issn:0862-8408

Subject:

svaly, muscles, CRF-R2, iris sphincter, ciliary muscle, urocortin 2, 14, and 612

Type:

model:article and TEXT

Format:

print, bez média, and svazek

Description:

Urocortin 2 (UCN2) is a peptide related to corticotropin-releasing factor, capable of activating CRF-R2. Among its multisystemic effects, it has actions in all 3 muscle subtypes. This study’s aim was to determine its potential role in two of the intrinsic eye muscle kinetics. Strips of iris sphincter (rabbit) and ciliary (bovine) muscles were dissected and mounted in isometric forcetransducer systems filled with aerated-solutions. Contraction was elicited using carbachol (10-6 M for iris sphincter, 10-5 M for ciliary muscle), prior adding to all testing substances. UCN2 induced relaxation in iris sphincter muscle, being the effect maximal at 10-7 M concentrations (-12.2 % variation vs. control). This effect was abolished with incubation of indomethacin, antisauvagine-30, chelerytrine and SQ22536, but preserved with L-nitro-L-arginine. In carbachol pre-stimulated ciliary muscle, UCN2 (10-5 M) enhanced contraction (maximal effect of 18.2 % increase vs. control). UCN2 is a new modulator of iris sphincter relaxation, dependent of CRF-R2 activation, synthesis of prostaglandins (COX pathway) and both adenylate cyclase and PKC signaling pathways, but independent of nitric oxide production. Regarding ciliary muscle, UCN2 enhances carbachol-induced contraction, in higher doses., M. Tavares-Silva, D. Ferreira, S. Cardoso, A. R. Raimundo, J. Barbosa-Breda, A. Leite-Moreira, A. Rocha-Sousa., and Obsahuje bibliografii

Language:

English

Rights:

http://creativecommons.org/publicdomain/mark/1.0/
policy:public

Source:

Physiological research | 2018 Volume:67 | Number:3

Harvested from:

CDK

Metadata only:

false