Figure 7
From: Functional NMDA receptors are expressed by human pulmonary artery smooth muscle cells
NMDA receptors regulate phenylephrine-induced pulmonary vasoconstriction. Precision-cut human lung slices containing pulmonary vessels were exposed to normoxic (21% O2) or hypoxic (5% O2) conditions overnight. The cells were pre-treated with 10 µM MK801 or vehicle (DMSO) for 1 h prior to adding varying concentrations of phenylephrine (PE), as indicated. (A) Phenylephrine induced pulmonary vasoconstriction in a dose-dependent manner in both normoxic and hypoxic conditions. (B) MK801 had little effect on maximal vasoconstriction (Emax) under normoxic conditions, but significantly attenuated maximal response to phenylephrine under hypoxic conditions (*p = 0.0231). (C) MK801 had little effect on the sensitivity of the pulmonary vessels to phenylephrine-measured by Log EC50 of the dose–response curve-in both conditions. (D) MK801 had little effect on area under the curve (AUC) of the phenylephrine dose–response curve in both conditions. (Data are representative of: Normoxic-Vehicle, n = 13 donors; Normoxic-MK801, n = 6 donors; Hypoxic-Vehicle, n = 13 donors; Hypoxic-MK801, n = 6 donors).
