Two classes of endothelin receptors mediating contraction in esophageal muscularis mucosae

Cysteinyl leucotriene receptor type 1 mediates contraction in human and guinea‐pig oesophagus

“…Measurements of contraction of isolated muscularis mucosae strips from the human and guinea‐pig oesophagus were performed according to the procedure published previously 26–28 . In brief, the guinea pig was killed and the oesophagus removed, cut longitudinally and washed.…”

“…The strips were connected to an isometric transducer (FT.03 Grass‐Telefactor; Astro‐Med, West Warwick, RI, USA), which was connected to an amplifier (Gould, Valley View, OH, USA) and a computer recording system (BIOPAC systems, Santa Barbara, CA, USA). The basal tension of the muscle strips was adjusted to 1.0 g for human and 0.5 g for guinea‐pig oesophageal muscularis mucosae strips 26,27 . Experiments were started after a 45‐min equilibration period.…”

“…Measurements of contraction of isolated muscularis mucosae strips from the human and guinea-pig oesophagus were performed according to the procedure published previously. [26][27][28] In brief, the guinea pig was killed and the oesophagus removed, cut longitudinally and washed. The guinea-pig oesophagus or human oesophagus, obtained from surgery, was placed in standard incubation solution, containing 118 mmol L )1 NaCl, 25 mmol L )1 NaHCO 3 , 4.7 mmol L )1 KCl, 14 mmol L )1 glucose, 1.2 mmol L )1 NaH 2 PO 4 , 1.8 mmol L )1 CaCl 2 , gassed with 95% O 2 -5% CO 2 .…”

“…The basal tension of the muscle strips was adjusted to 1.0 g for human and 0.5 g for guinea-pig oesophageal muscularis mucosae strips. 26,27 Experiments were started after a 45-min equilibration period. Carbachol (1 lmol L )1 )-induced contraction was used as a reference to express contractile response to agonists.…”

Muscularis mucosae - the forgotten sibling

“…Exogenously applied substance P and related tachykinins can produce a contraction of the muscularis mucosae via the stimulation of NK2-receptors (Kamikawa and Shimo, 1984;Daniel et al, 1989;Astolfi et al, 1993;Holzer and Holzer-Petsche, 1997;Kerr et al, 1997;Kerr et al, 2000). Esophageal muscularis mucosae had two types of endothelin receptors, ETA-and ETB-receptors whose were linked with the phospholipase C-protein kinase C pathway (Eglen et al, 1989;Uchida et al, 1998a;Uchida et al, 1998b;Huang, 2002). These receptors mediate tonic contractions predominantly by opening receptor-operated (store-operated) Ca 2+ channels and partly by opening T-type Ca 2+ channels, and mediate rhythmic motility by opening L-type Ca 2+ channels.…”