Higher Ca2+ -sensitivity of arterial contraction in 1-week-old rats is due to a greater Rho-kinase activity

• Verfasst von: Mochalov, S. V. [VerfasserIn]
• Verfasst von: Tarasova, N. V. [VerfasserIn]
• Verfasst von: Kudryashova, T. V. [VerfasserIn]
• Verfasst von: Gaynullina, Dina [VerfasserIn]
• Verfasst von: Kalenchuk, V. U. [VerfasserIn]
• Verfasst von: Borovik, Anatoly S. [VerfasserIn]
• Verfasst von: Vorotnikov, Alexander V. [VerfasserIn]
• Verfasst von: Tarasova, Olga S. [VerfasserIn]
• Verfasst von: Schubert, Rudolf [VerfasserIn]
• Titel: Higher Ca2+ -sensitivity of arterial contraction in 1-week-old rats is due to a greater Rho-kinase activity
• Verf.angabe: S.V. Mochalov, N.V. Tarasova, T.V. Kudryashova, D.K. Gaynullina, V.U. Kalenchuk, A.S. Borovik, A.V. Vorotnikov, O.S. Tarasova, R. Schubert
• E-Jahr: 2018
• Jahr: 31 January 2018
• Umfang: 15 S.
• Fussnoten: Gesehen am 30.04.2020 ; Im Titel ist "2+" hochgestellt
• Titel Quelle: Enthalten in: Acta physiologica
• Ort Quelle: Oxford [u.a.] : Wiley-Blackwell, 2006
• Jahr Quelle: 2018
• Band/Heft Quelle: 223(2018,3) Artikel-Nummer e13044, 15 Seiten
• ISSN Quelle: 1748-1716
• DOI: doi:10.1111/apha.13044
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Aging
• Sach-SW: Animals
• Sach-SW: Arteries
• Sach-SW: Calcium Signaling
• Sach-SW: Male
• Sach-SW: maturation
• Sach-SW: Methoxamine
• Sach-SW: Muscle, Smooth, Vascular
• Sach-SW: MYPT1
• Sach-SW: protein kinase C
• Sach-SW: Protein Kinase C
• Sach-SW: Rats, Wistar
• Sach-SW: rho-Associated Kinases
• Sach-SW: Rho-kinase
• Sach-SW: small arteries
• Sach-SW: smooth muscle
• Sach-SW: Vasoconstriction
• K10plus-PPN: 1696951607

Abstract

AIM: During early post-natal development, arterial contraction depends less on Ca2+ -signalling pathways but more on changes in Ca2+ -sensitivity compared to adult animals. Whether this difference is related to Rho-kinase, one of the major players affecting Ca2+ -sensitivity, is unknown for intact vessels. Thus, we tested the hypothesis that Rho-kinase critically contributes to the higher Ca2+ -sensitivity of contraction in intact arteries of 1-week-old rats. - METHODS: We studied 1-week-old, 4- to 5-week-old and 10- to 12-week-old rats performing isometric myography, Ca2+ -fluorimetry and Western blotting using intact saphenous arteries and arterial pressure measurements under urethane anaesthesia. - RESULTS: In 10- to 12-week-old rats, methoxamine (MX) produced vasoconstriction associated with an increase in [Ca2+ ]i and Ca2+ -sensitivity. In contrast, in 1-week-old rats these contractions were accompanied only by an increase in Ca2+ -sensitivity. All MX-induced effects were reduced by the Rho-kinase inhibitor Y-27632; this reduction was complete only in 1-week-old rats. The Rho-kinase specific site Thr855 on MYPT1 was increasingly phosphorylated by MX in vessels of 1-week-old, but not 10- to 12-week-old rats; this effect was also inhibited completely by Y-27632. The Rho-kinase inhibitor fasudil in a dose not affecting the pressor response to MX in 4- to 5-week-old rats reduced it considerably in 1-week-old rats. - CONCLUSION: Our results suggest that the higher Ca2+ -sensitivity of arterial contraction in 1-week-old compared to 10- to 12-week-old rats is due to a greater Rho-kinase activity. Constitutively active Rho-kinase contributes to MX-induced contraction in 10- to 12-week-old rats. In 1-week-old rats, additional Rho-kinase activation is involved. This remodelling of the Rho-kinase pathway is associated with its increased contribution to adrenergic arterial pressure responses.