Effect of nitric oxide on integrity, blood flow and cyclic GMP levels in the rat gastric mucosa: modulation by sialoadenectomy

Abstract

The effects of the nitrosothiol, S‐nitroso N‐acetylpenicillamine (SNAP) which liberates nitric oxide (NO), on ethanol‐mediated gastric damage, blood flow and cyclic GMP levels in siaoloadenectomized (SALX) rats have been investigated. Intraluminal instillation of ethanol (5–50% w/v) dose‐dependently induced haemorrhagic damage and decreased NO synthase activity in the gastric mucosa. Both the extent of mucosal damage and inhibition of NO synthase activity were exacerbated in SALX rats. Epidermal growth factor administration (5 and 10 μg kg−1, s.c.) reduced mucosal damage but did not restore NO synthase activity in ethanol‐treated SALX rats. SNAP infusion (0.01‐1.0 μg kg−1 min−1, i.v.) attenuated haemorrhagic damage in ethanol‐treated rats. The reduction in mucosal damage was significantly greater in SALX rats. SNAP administration also caused an increase in gastric mucosal blood flow and cyclic GMP levels in control rats and both responses were augmented in SALX animals. These data suggest that SALX is associated with increases in mucosal susceptibility to ethanol‐mediated damage and reduces mucosal NO synthase activity. Epidermal growth factor does not appear to influence mucosal NO synthase in ethanol‐treated rats. Furthermore, SALX augments the responsiveness of the gastric mucosa to NO administration. Therefore, factors from the salivary glands influence gastric NO formation and mucosal responsiveness to a NO donor.

Gastroprotective effects of Stachys Lavandulifolia extract on experimental gastric ulcer

“…In the present study, alcohol significantly reduced gastric mucosal NO level with increase mucosal injury compared to control group. These findings are in accordance with Trip and Tepperman's study in which they reported decreased NO biosynthesis along with mucosal damage (Tripp and Tepperman, 1995). In present study, it is assumed that NO increase followed by S. lavandulifolia extract intake can increase basal and stimulated vagus nerve tone and further acetylcholine effects on gastric muscular cells.…”

Role of prostaglandins and nitric oxide in gastric damage induced by metamizol in rats

“…Our results are supported by data indicating that a loss of compensatory action by cNOS may be responsible for the gastric mucosal injury caused by other NSAIDs such as indomethacin [41,42] and intraluminal instillation of ethanol [43]. During ischemia-reperfusion injury the activity of cNOS is also compromised [44,45].…”

Gastroprotective Potential Effects of Statins on Indomethacin-Induced Gastric Ulcers in Rats

“…In the present study, indomethacin significantly reduced gastric mucosal NO level compared to control group. These findings are in accordance with that of Trip and Tepperman who reported a decrease in NO biosynthesis, as a result of decreased NOS activity that was associated with an increase in the extent of the damage (41) . Treatment with atorvastatin significantly increased mucosal NO level when compared to indomethacin-treated rats.…”