Premium
Non‐specific gap junction action of connexin‐mimetic peptides in the rat basilar artery
Author(s) -
Haddock Rebecca Ellen,
Meaney Kate R,
Sandow Shaun L,
Hill Caryl E
Publication year - 2007
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.21.6.a911
Subject(s) - gap junction , connexin , vasomotion , basilar artery , hyperpolarization (physics) , carbenoxolone , endothelium , neuromuscular junction , microbiology and biotechnology , anatomy , cell junction , biophysics , chemistry , biology , medicine , cell , endocrinology , vasodilation , biochemistry , neuroscience , intracellular , organic chemistry , nuclear magnetic resonance spectroscopy
The present study examined Cx‐mimetic peptide ( 37,43 Gap27/ 40 Gap27) specificity in the isolated juvenile rat basilar artery exhibiting spontaneous vasomotion. Membrane potential, diameter and Ca 2+ dynamics were examined in intact and endothelium‐denuded arteries. Vessel anatomy and Cx expression was examined using ultrastructural and confocal immunohistochemistry. Separately, 37,43 Gap27 and 40 Gap27 abolished vasomotion and 40 Gap27 desynchronized adjacent smooth muscle cell [Ca 2+ ] i oscillations, similar to endothelial removal. However, peptides also reduced smooth muscle cell [Ca 2+ ] i oscillations and 37,43 Gap27 produced hyperpolarization. Control peptides also affected membrane potential and rhythmicity. Cx37 was present in both the muscle and endothelial cell layers, whilst Cx40 and 43 were detected in the endothelium. Myoendothelial gap junctions are comprised of Cxs37 and 40. Cx‐mimetic peptide effects in the rat basilar artery are not readily explained by specific action at gap junctions. Rather, in addition to gap junctional effects, the Cx‐mimetic peptides may act on ionic mechanisms unrelated to gap junction function; suggesting caution with their subsequent use in studies of cellular coupling.