Research Abstract |
The vascular system is a site of not only chemical but also mechanical reception, and these stimuli elicit subsequent cellular responses such as contraction and relaxation. The vascular tissues such as cerebral and coronary arteries and lymphaticus, which are particularly sensitive to stretch, possess structural similarities ; lowpitched muscular lining, well-developed caveola beneath the plasma membrane, and abundant mitochondria. The mechanical reception is more susceptible than pharmacological reception to chemical skinning, suggesting the importance of membrane lipids as a mechanosensor domain. Phospholipase C coupled to GTP-binding protein, possibly a G_q class, which is insensitive to cholera- or pertussis toxin, may play a role in the genesis of vascular tone produced by quick stretch. The vascular reactivity to a mechanical stimulus may be mediated through the pathways of Ca^<2+> signaling which are specific to the mechano-reception and common to a conventional vasoconstrictive agonist such as norepinephrine.
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