Figure 3. Comparison between responses to 50 mM K⁺_∘ and PGF in term human uterine smooth muscle.

Increasing [K⁺]_o to 50 mM evoked a membrane potential response which resembled a PG-induced action potential but hyperpolarization did not follow (upper traces). PGF alone (middle traces) or in solution containing 50 mM K⁺ (lower traces) evoked the usual action potential that was followed by hyperpolarization. All recordings were made in the same cell.