Neurokinin A suppresses a voltage-gated K+ current in smooth muscle cells from rat vas deferens
K Nakazawa, K Inoue, K Fujimori… - European journal of …, 1990 - Elsevier
K Nakazawa, K Inoue, K Fujimori, A Takanaka
European journal of pharmacology, 1990•ElsevierThe effects of neurokinin A (NKA) on freshly isolated smooth muscle cells from the rat vas
deferens were investigated electrophysiologically. NKA (10− 7 M) prolonged the duration of
action potentials without affecting resting potentials. Under voltage-clamp conditions, NKA
(10− 7 M) suppressed an outward K+ current activated by depolarizing voltage steps.
Substance P (SP, 10− 7 M) did not affect the K+ current, suggesting that NKA is more potent
in suppressing the K+ current than SP is, as is also true for the contractions of smooth …
deferens were investigated electrophysiologically. NKA (10− 7 M) prolonged the duration of
action potentials without affecting resting potentials. Under voltage-clamp conditions, NKA
(10− 7 M) suppressed an outward K+ current activated by depolarizing voltage steps.
Substance P (SP, 10− 7 M) did not affect the K+ current, suggesting that NKA is more potent
in suppressing the K+ current than SP is, as is also true for the contractions of smooth …
Abstract
The effects of neurokinin A (NKA) on freshly isolated smooth muscle cells from the rat vas deferens were investigated electrophysiologically. NKA (10−7 M) prolonged the duration of action potentials without affecting resting potentials. Under voltage-clamp conditions, NKA (10−7 M) suppressed an outward K+ current activated by depolarizing voltage steps. Substance P (SP, 10−7 M) did not affect the K+ current, suggesting that NKA is more potent in suppressing the K+ current than SP is, as is also true for the contractions of smooth muscles of the rat vas deferens. The suppression of the K+ conductance now reported may contribute to NKA-induced smooth muscle contraction.
Elsevier
