Endothelins promote egg albumin-induced intestinal anaphylaxis in rats Takeharu Shigematsu*, Soichiro Miura‡, Masahiko Hirokawa*, Ryota Hokari*, Hajime Higuchi*, Yoshikazu Tsuzuki*, Hiroyuki Kimura*, Ruri C. Nakatsumi*, Hiroshi Serizawa*, Hidetsugu Saito*, Hiromasa Ishii*  Gastroenterology  Volume 115, Issue 2, Pages 348-356 (August 1998) DOI: 10.1016/S0016-5085(98)70201-X Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 1 Time-course changes of ET-1 concentrations in the jejunal loops after EA challenge. Rats were sensitized by intraperitoneal injection of 10 μg of chicken EA and 10 mg of aluminum hydroxide as adjuvant (sensitized). Control rats were injected with material prepared in the same manner without antigen (control). Fourteen days later, intestinal loops were either challenged by adding 10 μg/mL EA to the perfusate or sham challenged by adding 10 μg/mL BSA to the perfusate. ET-1 concentrations of intestinal mucosa were determined by enzyme immunoassay. ●, Sensitized + EA; ■, sensitized + BSA; ○, control + EA. Values are expressed as means ± SEM of six experiments. *P < 0.05 vs. control + EA; †P < 0.05 vs. sensitized + BSA. Gastroenterology 1998 115, 348-356DOI: (10.1016/S0016-5085(98)70201-X) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 2 Time-course changes of ET-3 concentrations in the jejunal loops after EA challenge. Rats were sensitized by chicken EA. Fourteen days later, intestinal loops were challenged by adding EA or BSA to the perfusate. ET-3 concentrations of intestinal mucosa were determined by enzyme immunoassay. ●, Sensitized + EA; ■, sensitized + BSA; ○, control + EA. Values are expressed as means ± SEM of six experiments. *P < 0.05 vs. control + EA; †P < 0.05 vs. sensitized + BSA. Gastroenterology 1998 115, 348-356DOI: (10.1016/S0016-5085(98)70201-X) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 3 ET-1 mRNA expression in control animals and in sensitized animals after 1 hour of EA challenge into the jejunal loop as determined by competitive RT-PCR. A specific band for ET-1 mRNA is expressed at 543 bp. The PCR MIMIC product was designed at 340 bp. Expression of ET-1 mRNA was increased in sensitized animals challenged with EA compared with control animals. HaeIII: molecular weight standard, ΦX-174RF DNA-HaeIII digest. Gastroenterology 1998 115, 348-356DOI: (10.1016/S0016-5085(98)70201-X) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 4 ET-3 mRNA expression in control animals and in sensitized animals after 1 hour of EA challenge to the jejunal loop as determined by competitive RT-PCR. A specific band for ET-3 mRNA is expressed at 477 bp. The PCR MIMIC product is at 340 bp. Expression of ET-3 mRNA was increased in sensitized animals challenged with EA compared with control animals. Gastroenterology 1998 115, 348-356DOI: (10.1016/S0016-5085(98)70201-X) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 5 Serum concentrations of RMCP-II in portal venous blood in intestinal anaphylaxis after EA challenge. Fourteen days after sensitization with EA, intestinal loops were challenged by EA or BSA. RMCP-II concentration was determined by enzyme-linked immunosorbent assay. In some experiments, sensitized animals were treated with the ETA-receptor antagonist BQ-123 (0.1 mg · kg−1 · min−1 intravenously [IV]), the ETA/ETB–receptor antagonist bosentan (30 mg/kg per os and 10 mg/kg IV), or the ETB-receptor antagonist BQ-788 (10 nmol · kg−1 · min−1 IV) before EA challenge. Values are expressed as means ± SEM of six experiments. *P < 0.05 vs. control + EA; †P < 0.05 vs. sensitized + BSA; #P < 0.05 vs. sensitized + EA. Gastroenterology 1998 115, 348-356DOI: (10.1016/S0016-5085(98)70201-X) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 6 Time-course changes in net water flux in jejunal loops in intestinal anaphylaxis after EA challenge. (A) Rats were sensitized with EA or injected with alum alone. Fourteen days later, intestinal loops were either challenged by EA or BSA. (B) In some experiments, sensitized animals were treated with BQ-123; 0.1 mg · kg−1 · min−1 IV), bosentan (30 mg/kg per os and 10 mg/kg IV), or BQ-788 (10 nmol · kg−1 · min−1 IV) before EA challenge. Values are expressed as means ± SEM of six experiments. *P < 0.05 vs. control + EA; †P < 0.05 vs. sensitized + BSA; #P < 0.05 vs. sensitized + EA. Gastroenterology 1998 115, 348-356DOI: (10.1016/S0016-5085(98)70201-X) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 6 Time-course changes in net water flux in jejunal loops in intestinal anaphylaxis after EA challenge. (A) Rats were sensitized with EA or injected with alum alone. Fourteen days later, intestinal loops were either challenged by EA or BSA. (B) In some experiments, sensitized animals were treated with BQ-123; 0.1 mg · kg−1 · min−1 IV), bosentan (30 mg/kg per os and 10 mg/kg IV), or BQ-788 (10 nmol · kg−1 · min−1 IV) before EA challenge. Values are expressed as means ± SEM of six experiments. *P < 0.05 vs. control + EA; †P < 0.05 vs. sensitized + BSA; #P < 0.05 vs. sensitized + EA. Gastroenterology 1998 115, 348-356DOI: (10.1016/S0016-5085(98)70201-X) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 7 Time-course changes in histamine release in jejunal loops in intestinal anaphylaxis after EA challenge. Histamine concentrations in the effluent collected were determined by radioimmunoassay. (A) Rats were sensitized with EA or injected with alum alone (control). Fourteen days later, intestinal loops were challenged by EA or BSA. (B) In some experiments, sensitized animals were treated with BQ-123, bosentan, or BQ-788 before EA challenge. Values are expressed as means ± SEM of six experiments. *P < 0.05 vs. control + EA; †P < 0.05 vs. sensitized + BSA; #P < 0.05 vs. sensitized + EA. Gastroenterology 1998 115, 348-356DOI: (10.1016/S0016-5085(98)70201-X) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 7 Time-course changes in histamine release in jejunal loops in intestinal anaphylaxis after EA challenge. Histamine concentrations in the effluent collected were determined by radioimmunoassay. (A) Rats were sensitized with EA or injected with alum alone (control). Fourteen days later, intestinal loops were challenged by EA or BSA. (B) In some experiments, sensitized animals were treated with BQ-123, bosentan, or BQ-788 before EA challenge. Values are expressed as means ± SEM of six experiments. *P < 0.05 vs. control + EA; †P < 0.05 vs. sensitized + BSA; #P < 0.05 vs. sensitized + EA. Gastroenterology 1998 115, 348-356DOI: (10.1016/S0016-5085(98)70201-X) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 8 ETA- and ETB-receptor mRNA expression in the rat mucosal mast cell line RBL-2H3 as determined by RT-PCR. A specific band for ETA-receptor mRNA was expressed at 418 bp, but there was no ETB-receptor mRNA expressed in this cell line. Gastroenterology 1998 115, 348-356DOI: (10.1016/S0016-5085(98)70201-X) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 9 Effect of ET-1 on RMCP-II release into the culture supernatant of the mucosal mast cell line RBL-2H3 in vitro, and the attenuating effects of BQ-123 and bosentan. ET-1 (10−9 mol/L) was added to the culture medium containing 5% FCS. At different time intervals (1–12 hours), culture supernatant was collected and RMCP-II concentrations were determined by enzyme-linked immunosorbent assay. BQ-123 (100 nmol/L) and bosentan (10 μmol/L) were added to culture media along with ET. Values are expressed as means ± SEM of six experiments. *P < 0.05 vs. control; #P < 0.05 vs. ET-1 alone. Gastroenterology 1998 115, 348-356DOI: (10.1016/S0016-5085(98)70201-X) Copyright © 1998 American Gastroenterological Association Terms and Conditions

Fig. 10 Effect of IgE administration on ET-1 mRNA expression in the rat mucosal mast cell line RBL-2H3 as determined by RT-PCR. A specific band for ET-1 mRNA is expressed at 543 bp. Rat IgE was added to culture media containing 5% FCS at a concentration of 0.8 μg/mL. After 1 and 2 hours, expression of ET-1 mRNA was increased compared with controls (0 h). Gastroenterology 1998 115, 348-356DOI: (10.1016/S0016-5085(98)70201-X) Copyright © 1998 American Gastroenterological Association Terms and Conditions