In:
American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, American Physiological Society, Vol. 294, No. 1 ( 2008-01), p. R1-R11
Kurzfassung:
Our previous data indicated that various subtypes of connexin (Cx) were expressed in the juxtaglomerular apparatus. Experiments were performed to characterize the effects on renal autoregulation of specific mimetic peptides that inhibit these Cx subtypes in Wistar-Kyoto rats. Intrarenal infusion of Cx37,43 GAP27 increased autoregulatory index of renal plasma flow (0.06 ± 0.05 to 0.47 ± 0.06, n = 6, P 〈 0.05) and glomerular filtration rate (GFR; 0.01 ± 0.07 to 0.49 ± 0.07, P 〈 0.05). The additional administration of 8-cyclopentyl- 1,3-dipropylxanthine (CPX) produced a further elevation of autoregulatory index of RPF (0.86 ± 0.07, P 〈 0.05) and GFR (0.88 ± 0.09, P 〈 0.05), compared with Cx37,43 GAP27 alone. However, the addition of pyridoxal-phosphate-6-azophenyl-2,4-disulfonic acid (PPADS) to Cx37,43 GAP27 did not. Combined treatment with CPX and PPADS markedly worsened autoregulatory index of RPF (0.04 ± 0.10 to 0.81 ± 0.06, n = 6 P 〈 0.01) and GFR (0.05 ± 0.08 to 0.79 ± 0.05, P 〈 0.01). Cx40 GAP27 induced similar changes to Cx37,43 GAP27. Renal autoregulation was preserved in the presence of Cx43 GAP26. Our results indicate that the inhibition of gap junction impaired renal autoregulation. Furthermore, the present data provide evidence that both adenosine and purinergic receptors contribute to glomerular autoregulation. Finally, our findings suggest that gap junctions, at least in part, transduce purinergic signals mediating renal autoregulation.
Materialart:
Online-Ressource
ISSN:
0363-6119
,
1522-1490
DOI:
10.1152/ajpregu.00269.2007
Sprache:
Englisch
Verlag:
American Physiological Society
Publikationsdatum:
2008
ZDB Id:
1477297-8
SSG:
12
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