Inhibition of ADP-mediated constriction of vascular smooth muscle and enhancement of adenosine-induced coronary blood-flow are also reported.
Others have described A1-receptor-mediated constriction of renal afferent arterioles in normal animals (Tagawa and Vander, 1970; Webb et al., 1990; Tang et al., 1999), and here we also found that, in the control animals, adenosine caused some fall in renal vascular conductance prior to the development of the vasodilatation.
Meningeal and cortical CAA contribute to white matter ischaemia, and reduced perfusion of the white matter in Alzheimer's disease may also result from angiotensin II- and ET1-mediated constriction of perforating arterioles that traverse the cortex, but supply blood to the white matter.
We have demonstrated that Ang-II and NO exhibit their vasoactive effects specifically via pericytes (Crawford et al. 2012), and Ang-II-mediated constriction of DVR in medullary ray tissue strips is attenuated by NO released from neighbouring mTAL epithelium (Dickhout et al. 2002).
While this differential involvement of PKC is interesting, particularly since it too is implicated in ROS-mediated constriction, further analysis of the role of PKC in this constriction is beyond the scope of this study.
Together, these results suggest that the changes in cell shape associated with EPI polarization are mediated by actomyosin-mediated constriction coupled to apical localization of the adherens junctions.
Crawford et al. (2011) have demonstrated ATP- and uridine triphosphate (UTP -mediated constriction and dilation of in sitUTP -mediated speconstriction pericyte sites (Crandordilation 2011).
Reduced NE-induced constriction in BHR may result from augmented sensitivity and number of β-2 adrenergic receptors due to elevated corticosterone [ 59] which may blunt α-1 adrenergic receptor-mediated constriction.
Interestingly, VP-mediated constriction was reduced by age in F, but was unchanged in M rats.
The methods used in our laboratory to assess FMD and flow-mediated constriction (L-FMC) have been recently described.
