Physiological Roles of N-Methyl-D-Aspartate (NMDA) or / and Glycine on The Stomach
Abstract
In this study, NMDA (N-methyl-D-aspartate) or with glycine (glycine) For rats in vitro
Rat gastric acid secretion and gastric ulcer in mice on the impact of stress.
In the rat isolated perfused rat stomach glycine 10 ^ -6 M and 10 ^ -2 M can stimulate gastric acid secretion, and in 10 ^ -3 M can be
Spontaneous gastric acid secretion up to 1.6 times the maximum stimulating effect is. Stimulation of acid secretion can be
strychnine, atropine, tetrodotoxin, bicuculline and inhibited by proglumide. But not
By cimetidine. However, the separate perfusion NMDA 10 ^ -4 M and 10 ^ -5 M when the spontaneous acid
No effect on secretion, but reduced the oxotremorine-induced gastric acid secretion, and this effect may be due to glycine
10 ^ -6 M to join and strengthen its inhibitory effect, but this
strengthening effect can not be antagonized by strychnine. Another
Applications of NMDA on the role of stress ulcer and cAMP / cGMP ratio (cAMP / cGMP ratio) changes
To infer the NO and the protective effect of glycine in this role. The results showed that the pressure of time in different gastric ulcer
Ulcers of the degree of cAMP / cGMP ratio is proportional. When the abdominal cavity cast and NMDA 0.2mg / kg-2mg / kg, the lower Pressure ulcer area showed high correlation (r = 0.779, P <0.001), and in the 1 mg / kg, the right lower collapse
Ulcer area produces up to 70% of the preventive effect; this when the rat stomach ulcers reduce cAMP / cGMP ratio decreased with increasing
. If the same cast with the NMDA and glycine can enhance the protection of pressure ulcers, and in L-NNA (NO synthase
inhibitor) 10mg / kg of pressure when the role of NMDA antagonism.
These results were found, and glycine stimulate gastric acid
secretion may be mainly induced by cholinergic nerve conductivity (
cholinergic neuron) on the on the strychnine-sensitive glycine receptor (strychnine-sensitive
glycine sites) To regulate gastric acid secretion. On the other hand, NMDA reduced the oxotremorine induced
Of gastric acid secretion, and glycine on strychnine via non- sensitive glycine receptor (strychnine-
insensitive glycine sites) to regulate NMDA receptor (NMDA receptor) activity. In addition,
NMDA in the pressure ulcer may be involved in gastric mucosal barrier (mucosal barrier) The physiological regulation. The mechanism
Could be due to promote the release of endogenous NO, and
reduce the cAMP / cGMP ratio; while the glycine in this study may be
NMDA receptor activity involved in the regulation of endogenous substances (endogenous ligand).
English Abstract
