The Excitatory Mechanism of Substance P in the Antral Circular Muscle of Guinea Pig Stomach

• 영문명: The Excitatory Mechanism of Substance P in the Antral Circular Muscle of Guinea Pig Stomach
• 발행기관: 대한생리학회
• 저자명: Jun, Jae-Yeoul Kim, Sung-Joon Choi, Youn-Baik Kim, Ki-Whan
• 간행물 정보: 『대한생리학회지』제28권 제1호, 51~60쪽, 전체 10쪽
• 주제분류: 의약학 > 의학일반
• 파일형태: PDF
• 발행일자: 1994.06.30

영문 초록

This study was carried out to elucidate the excitatory mechanisms of Substance P in the antral circular muscle, using isometric contraction recording, conventional microelectrode method and whole-cell patch clamp technique. Substance P produced tonic and phasic contractions in a dose-dependent manner and depolarized membrane potential with increased amplitude of slow waves in muscle strips. Voltage-dependent Ca²⁺ currents were increased by the application of Substance P from a holding potential of -60mV to 50mV in 10mV steps and this effect was blocked by the addition of an antagonist. Also Substance P increased transient and spontaneous oscillatory K⁺ outward currents. The enhanced outward currents were abolished by apamin in dispersed single cells. These results suggest that the depolarization of membrane potential by Substance P activates voltage-dependent Ca²⁺ channels, which represents an excitatory response in the antral circular muscle and led to an increase in Ca²⁺ activated K⁺ currents

키워드

Slow wave Antral myocytes Substance P Voltage-dependent Ca²⁺ currents Ca²⁺ activated K⁺ currents