H2 Receptor-Mediated Relaxation of Circular Smooth Muscle in Human Gastric Corpus: the Role of Nitric Oxide (NO)
The Korean Journal of Physiology and Pharmacology
; : 425-430, 2014.
Article
in En
| WPRIM
| ID: wpr-727704
Responsible library:
WPRO
ABSTRACT
This study was designed to examine the effects of histamine on gastric motility and its specific receptor in the circular smooth muscle of the human gastric corpus. Histamine mainly produced tonic relaxation in a concentration-dependent and reversible manner, although histamine enhanced contractility in a minor portion of tissues tested. Histamine-induced tonic relaxation was nerve-insensitive because pretreatment with nerve blockers cocktail (NBC) did not inhibit relaxation. Additionally, K+ channel blockers, such as tetraethylammonium (TEA), apamin (APA), and glibenclamide (Glib), had no effect. However, N(G)-nitro-L-arginine methyl ester (L-NAME) and 1H-(1,2,4)oxadiazolo (4,3-A) quinoxalin-1-one (ODQ), an inhibitor of soluble guanylate cyclase (sGC), did inhibit histamine-induced tonic relaxation. In particular, histamine-induced tonic relaxation was converted to tonic contraction by pretreatment with L-NAME. Ranitidine, the H2 receptor blocker, inhibited histamine-induced tonic relaxation. These findings suggest that histamine produced relaxation in circular smooth muscle of human gastric smooth muscle through H2 receptor and NO/sGC pathways.
Key words
Full text:
1
Database:
WPRIM
Main subject:
Apamin
/
Ranitidine
/
Relaxation
/
Receptors, Histamine H2
/
Histamine
/
Glyburide
/
NG-Nitroarginine Methyl Ester
/
Tetraethylammonium
/
Guanylate Cyclase
/
Muscle, Smooth
Limits:
Humans
Language:
En
Journal:
The Korean Journal of Physiology and Pharmacology
Year:
2014
Document type:
Article