01 January 2000
Stimulation by nitric oxide of HCO3- secretion in bullfrog duodenum in vitro - role of cyclooxygenase-1 and prostaglandins
Osamu Furukawa, Shoji Kawauchi, Hiroshi Mimaki, Koji TakeuchiMed Sci Monit 2000; 6(3): BR454-459 :: ID: 421326
Abstract
The effect of nitric oxide (NO) on HCO3- secretion was examined in vitrousing the isolated preparation of bullfrog duodenum, in relation to cyclooxygenase (COX) isozymes andendogenous prostaglandins (PGs). The tissue was bathed in unbuffered Ringer solution gassed with 100%O2 on the mucosal side and HCO3- Ringer's solution gassed with 95% O2-5% CO2 on the serosal side. TheHCO3- secretion was measured by a pH-stat method using 10 mM HCl as the titrant to keep the mucosal pHat 7.4. NOR-3 [(+/-)-(E)-Ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamine] was used as a NO donor andadded to the serosal solution. To analyze the NOR-3 action, the effects of dibutyryl guanosine-3', 5'-cyclicmonophosphate (dbcGMP), methylene blue, indomethacin (nonselective COX-inhibitor) and NS-398 (selectiveCOX-2 inhibitor) on the HCO3- response were also examined. NOR-3 (1 x 10(-4) and 3 x 10(-4) M) causedan increase of HCO3- secretion in a dose-dependent manner, reaching the level of 2.5 times greater thanbasal values at 2 hr later. Likewise, dbcGMP (1 x 10(-3) M) also caused a significant increase of theduodenal HCO3- secretion. The HCO3- stimulatory action of NOR-3 was significantly attenuated by methyleneblue (5 x 10(-5) M) and indomethacin (1 x 10(-5) M) but not by NS-398 (1 x 10(-5) M), and indomethacinalso suppressed the HCO3- response to dbcGMP. The serosal release of PGE2 was significantly increasedby both NOR-3 and dbcGMP, and these responses were inhibited by indomethacin but not NS-398. These resultssuggest that NO increases HCO3- secretion in Bullfrog duodenum in vitro, and this action is dependenton cGMP-related COX-1 activation and mediated by PGs.
Keywords: 16,16-Dimethylprostaglandin E2, Bicarbonates, Cyclooxygenase Inhibitors, Dibutyryl Cyclic GMP, Dinoprostone, Duodenum, Indomethacin, Intestinal Mucosa, Isoenzymes, Kinetics, Methylene Blue, Nitric Oxide Donors, Nitro Compounds, Nitrobenzenes, Prostaglandin-Endoperoxide Synthase, Prostaglandins, Rana catesbeiana, Sulfonamides
Editorial
01 April 2024 : Editorial
Editorial: Forty Years of Waiting for Prevention and Cure of HIV Infection – Ongoing Challenges and Hopes for Vaccine Development and Overcoming Antiretroviral Drug ResistanceDOI: 10.12659/MSM.944600
Med Sci Monit 2024; 30:e944600
In Press
08 Mar 2024 : Clinical Research
Evaluation of Foot Structure in Preschool Children Based on Body MassMed Sci Monit In Press; DOI: 10.12659/MSM.943765
15 Apr 2024 : Laboratory Research
The Role of Copper-Induced M2 Macrophage Polarization in Protecting Cartilage Matrix in OsteoarthritisMed Sci Monit In Press; DOI: 10.12659/MSM.943738
07 Mar 2024 : Clinical Research
Knowledge of and Attitudes Toward Clinical Trials: A Questionnaire-Based Study of 179 Male Third- and Fourt...Med Sci Monit In Press; DOI: 10.12659/MSM.943468
08 Mar 2024 : Animal Research
Modification of Experimental Model of Necrotizing Enterocolitis (NEC) in Rat Pups by Single Exposure to Hyp...Med Sci Monit In Press; DOI: 10.12659/MSM.943443
Most Viewed Current Articles
17 Jan 2024 : Review article
Vaccination Guidelines for Pregnant Women: Addressing COVID-19 and the Omicron VariantDOI :10.12659/MSM.942799
Med Sci Monit 2024; 30:e942799
14 Dec 2022 : Clinical Research
Prevalence and Variability of Allergen-Specific Immunoglobulin E in Patients with Elevated Tryptase LevelsDOI :10.12659/MSM.937990
Med Sci Monit 2022; 28:e937990
16 May 2023 : Clinical Research
Electrophysiological Testing for an Auditory Processing Disorder and Reading Performance in 54 School Stude...DOI :10.12659/MSM.940387
Med Sci Monit 2023; 29:e940387
01 Jan 2022 : Editorial
Editorial: Current Status of Oral Antiviral Drug Treatments for SARS-CoV-2 Infection in Non-Hospitalized Pa...DOI :10.12659/MSM.935952
Med Sci Monit 2022; 28:e935952