Association of CaV1.3 L-type calcium channels with Shank - PubMed (original) (raw)

Effects of R9 competitive peptides on L-type Ca2+ channels mediated pCREB signaling. A, Loading of FITC-conjugated R9, R9-LCC, R9-LDC, and R9-NR2B peptides into mature hippocampal neurons was visualized by FITC fluorescence. B, Hippocampal neurons loaded with R9, R9-LCC, and R9-LDC peptides were stimulated 3 h after loading for 60 s by 20 m

m

KCl (20 K) or 45 m

m

KCl (45 K) in the presence of 1 μ

m

TTX, 50 μ

m d

-AP-5, and 10 μ

m

CNQX. An average peak 340/380 fura-2 ratio is shown as a function of stimulus intensity for neurons loaded with R9 (filled circles; n = 18), R9-LCC (open circles; n ≥ 17), and R9-LDC (filled triangles; n ≥ 15). C, The hippocampal neurons loaded with R9, R9-LCC, R9-LDC, R9-LDC plus R9-LCC, and R9-NR2B peptides were stimulated 3 h after loading for 90 s by 20 m

m

KCl (20 K) or 45 m

m

KCl (45 K) in the presence of 1 μ

m

TTX, 50 μ

md

-AP-5, and 10 μ

m

CNQX and fixed and stained with anti-pCREB pAb. Confocal images of pCREB staining in stimulated and unstimulated neurons (no stim) are shown. D, E, An average stimulation-induced increase in normalized pCREB nuclear staining (ΔpCREB) is shown as a function of stimulus intensity for control neurons (open circles; n ≥ 70), for neurons loaded with R9 (open squares; n ≥ 118), R9-NR2B (filled squares; n ≥ 55), R9-LCC (open downward triangles; n ≥ 87), R9-LDC (filled circles; n ≥ 72), and R9-LCC plus R9-LDC mixture (open upward triangles;n ≥ 78). At 20K stimulation, the increase in pCREB staining in R9-loaded neurons is significantly higher (***p < 0.05) than in R9-LCC or R9-LDC-loaded neurons. At 45K stimulation, the increase in pCREB staining in R9-loaded neurons is significantly higher than in R9-LCC-loaded neurons but not in R9-LDC-loaded neurons.