Correction

PHARMACOLOGY. For the article “5-Methyltetrahydrofolate and tetrahydrobiopterin can modulate electrotonically mediated endothelium-dependent vascular relaxation,” by Tudor M. Griffith, Andrew T. Chaytor, Linda M. Bakker, and David H. Edwards, which appeared in issue 19, May 10, 2005, of Proc. Natl. Acad. Sci. USA (102, 7008-7013; first published May 2, 2005; 10.1073/pnas.0408919102), the authors note that previously published data had been included in error. Specifically, in Fig. 3A of the PNAS article, representative traces of the endothelial cell patch clamp data were identical to those in figure 2A of ref. 4. The corrected figure and its legend appear below.

Fig. 3.

Electrophysiological studies with connexin-mimetic peptides. (A) Whole-cell patch-clamp recordings and histogram confirming that 600 μM ^37,40Gap 26 and 100 μM ⁴³Gap 26 did not depress endothelial hyperpolarizations evoked by 30 μM CPA. (B and C) Original recordings and histograms comparing the effects of the peptides and 2,000 units/ml catalase on subintimal (B) and subadventitial (C) hyperpolarizations evoked by CPA. ^37,40Gap 26 attenuated the transmission of endothelial hyperpolarization to subintimal smooth muscle, whereas ⁴³Gap 26 selectively impaired transmission of subintimal hyperpolarization across the vessel wall. The effects of both peptides were prevented by 100 μM 5-MTHF and (6R)-BH₄ but not by 100 μM FA or BH₂. Catalase prevented the effects of ^37,40Gap 26 on subintimal hyperpolarization, but not those of ⁴³Gap 26 on subadventitial hyperpolarization. ^*, P < 0.05, compared with control.