Inhibition of gastric acid secretion by stress: A protective reflex mediated by cerebral nitric oxide
AUTOR(ES)
Esplugues, J. V.
FONTE
The National Academy of Sciences of the USA
RESUMO
Moderate somatic stress inhibits gastric acid secretion. We have investigated the role of endogenously released NO in this phenomenon. Elevation of body temperature by 3°C or a reduction of 35 mmHg (1 mmHg = 133 Pa) in blood pressure for 10 min produced a rapid and long-lasting reduction of distension-stimulated acid secretion in the rat perfused stomach in vivo. A similar inhibitory effect on acid secretion was produced by the intracisternal (i.c.) administration of oxytocin, a peptide known to be released during stress. Intracisternal administration of the NO-synthase inhibitor, NG-nitro-l-arginine methyl ester (l-NAME) reversed the antisecretory effect induced by all these stimuli, an action prevented by intracisternal coadministration of the NO precursor, l-arginine. Furthermore, microinjection of l-NAME into the dorsal motor nucleus of the vagus nerve reversed the acid inhibitory effects of mild hyperthermia, i.v. endotoxin, or i.c. oxytocin, an action prevented by prior microinjection of l-arginine. By contrast, microinjection of l-NAME into the nucleus tractus solitarius failed to affect the inhibitory effects of hyperthermia, i.v. endotoxin, or i.c. oxytocin. Immunohistochemical techniques demonstrated that following hyperthermia there was a significant increase in immunoreactivity to neuronal NO synthase in different areas of the brain, including the dorsal motor nucleus of the vagus. Thus, our results suggest that the inhibition of gastric acid secretion, a defense mechanism during stress, is mediated by a nervous reflex involving a neuronal pathway that includes NO synthesis in the brain, specifically in the dorsal motor nucleus of the vagus.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=26223Documentos Relacionados
- Nitric oxide-an endogenous inhibitor of gastric acid secretion in isolated human gastric glands
- Stimulation of renin secretion by nitric oxide is mediated by phosphodiesterase 3
- Osteoclastic inhibition: an action of nitric oxide not mediated by cyclic GMP.
- Nitric oxide mediates cytokine-induced inhibition of insulin secretion by human islets of Langerhans.
- Piper sarmentosum increases nitric oxide production in oxidative stress: a study on human umbilical vein endothelial cells