The contribution of protein kinase C and rho-kinase to the regulation of receptor-dependent contraction of arteries decreases with age independently of sympathetic innervation

Antenatal/early postnatal hypothyroidism alters arterial tone regulation in 2-week-old rats

“…Rho-kinase is a key determinant of Ca 2+ sensitivity of arterial smooth muscle contraction and its expression level and functional role are augmented in early postnatal period (Akopov et al 1998, Mochalov et al 2008, Puzdrova et al 2014. In the present study, we showed for the first time that antenatal/early postnatal hypothyroidism may stimulate the expression of Rho-kinase and activity of this signaling pathway in mesenteric arteries of 2-week-old animals.…”

“…Smooth muscle in developing vessels has a strongly augmented Ca 2+ sensitivity of contractile apparatus, which compensates for the deficiency of Ca 2+ -dependent control of smooth muscle contraction (Sandoval et al 2007, Puzdrova et al 2014. Such Ca 2+ -sensitization is due to enhanced contribution of Rho-kinase in contractile responses of arteries during early postnatal period (Akopov et al 1998, Mochalov et al 2008. Another important vasomotor feature of the developing vasculature is NO-mediated anticontractile effect of the endothelium that is prominent in early postnatal period and gradually decreases with maturation (Gaynullina et al 2013, Sofronova et al 2016.…”

Trophic action of sympathetic nerves reduces arterial smooth muscle Ca2+sensitivity during early post-natal development in rats

“…The expression levels of RhoK did not differ between denervated and control arteries. In line with this finding, Y27632, a RhoK inhibitor, similarly affected methoxamine-induced contractions of saphenous arteries in rats 2 weeks after denervation and in sham-operated rats (Mochalov et al 2008), pointing to an unchanged RhoK activity. However, our preliminary data suggest that an increase of RhoK expression may take place after denervation of longer duration; this interesting new aspect has to be addressed in a subsequent study.…”

“…While a similar reduction in the ERK1/2 protein level has been reported in developing ovine carotid arteries (Pearce et al 2003), such changes have not yet been described, to the best of our knowledge, for p38 MAPK and RhoK. Notably, inhibition of RhoK activity results in a more prominent depression of contraction in developing saphenous arteries than in arteries from adults rats (Mochalov et al 2008).…”