Effects of galanin on the opossum internal anal sphincter: Structure-activity relationship

摘要: The present study was carried out to investigate the effects of porcine galanin-(1–29), N-terminal fragment galanin-(1–10), C-terminal galanin(15–29), and middle galanin-(7–16) on spontaneous tension opossum internal anal sphincter decrease in resting response neural stimulation by electrical field stimulation. Galanin galanin-(1–10) caused a concentration-dependent an augmentation percent with Galanin-(15–29), other hand, produced increase had no effect stimulation—induced tension. Galanin-(7–16) significant sphincter. galanin partially antagonized tetrodotoxin, whereas galanin(15–29) not modified tetrodotoxin. In contrast its sphincter, suppressed lower esophageal From these findings we conclude that (a) exerts inhibitory on. activating receptors both at intramural neurons smooth muscle portion may be responsible for actions; (b) contractile action is muscle; (c) actions gastrointestinal tract are tissue specific.