Updated publication reference for PubMed record(s): 34301959. Pannexin 1 (Panx1) channels can be activated by alpha 1 adrenoceptor-induced pathways for the sympathetic regulation of blood pressure; however, the molecular mechanisms for this form of Panx1 channel activation remain elusive. To identify potential acetyl-lysine residue(s) of Panx1 channels that might be involved in this receptor-mediated Panx1 channel activation, we performed mass-spectrometry on Strep-tagged Panx1 proteins precipitated from the whole cell lysate of HEK293T cells after stable isotope labeling by amino acids in cell culture (SILAC). Those HEK293T cells were transiently transfected with alpha1D adrenoceptors and human Panx1-Strep, with or without phenylephrine stimulation. Equal amounts of light-labeled (control) and heavy-labeled (phenylephrine stimulated) cell lysates were pooled, and Panx1 proteins were precipitated by Strep-Tactin beads, followed by LC-MS-MS analysis. From three biological replicates, we identified a consistent, albeit modest, reduction of acetylation level at K140, following phenylephrine stimulation. Whereas the acetylation level of other lysine residues (K321, K374, K381, K409) were variable among three replicates or were unaffected by phenylephrine treatment. These results implicate Panx1 K140 as a potential regulatory site for receptor-mediated channel activation via an acetylation-deacetylation mechanism.