Role of sarcoplasmic reticulum in the myorelaxant activity of nitric oxide donors in guinea pig gastric fundus.

  title={Role of sarcoplasmic reticulum in the myorelaxant activity of nitric oxide donors in guinea pig gastric fundus.},
  author={Georgi V. Petkov and G Spassov and Kiril K. Boev},
  journal={European journal of pharmacology},
  volume={354 1},
Mechanism of a nitric oxide donor NOR 1-induced relaxation in longitudinal muscle of rat proximal colon.
The results suggest that nitric oxide induces the relaxation preferentially by acting thapsigargin-sensitive function of SR and in turn decreasing [Ca2+]i, although a cyclic GMP-PKG pathway is suggested under the experimental conditions of a high K+ concentration.
The reactivity of serotonin, acetylcholine and kcl-induced contractions to relaxant agents in the rat gastric fundus.
The effects of nifedipine, cromakalim, diazoxide, caffeine and sodium nitroprusside (SNP) on acetylcholine, serotonin and KCl-induced contractions were studied in rat stomach fundus. Thus, we aimed
Role of calcium mobilization in sodium nitroprusside-induced increase of calcium-activated potassium currents in gastric antral circular myocytes of guinea pig.
The increase of IK(Ca) caused by SNP may be mediated by cGMP via IP3-sensitive calcium pools, however, extracellular Ca2+ may not be involved in the process.
Stimulatory effects of nitric oxide donors on histamine release in isolated rat gastric mucosal cells.
It is suggested that NO donors act on cyclic GMP pathway in isolated gastric mucosal cells, resulting in facilitation of histamine release, which may stimulate gastric acid secretion through histamines release from the histamine-containing cells.
Induction of heme oxygenase in guinea-pig stomach: roles in contraction and in single muscle cell ionic currents.
This is the first study demonstrating that heme oxygenase is an inducible enzyme in guinea-pigs, which exerts a modulatory role on gastric smooth muscle excitability via carbon monoxide production.
Actions of putative chloride channel blocking agents on canine lower esophageal sphincter (LES)
NA is an unreliable pharmacological tool to evaluate Cl(-)-channel contributions to smooth muscle function and does not inhibit NO-mediated relaxations, but does open K+ channels.
Ion channels in smooth muscle: regulators of intracellular calcium and contractility.
The literature suggests that in SM Ca2+ released from the SR functions to limit contractility, and this is part of a negative feedback mechanism limiting contraction that occurs by the Ca2-dependent activation of large-conductance K+ channels, which hyper polarize the plasma membrane.
Nitrergic Neurotransmission in the Enteric Nervous System
This chapter will focus on the characteristics of nitrergic neurotransmission, and it must be clearly stated, however, that although nitric oxide (NO) is an important enteric neurotransmitter, it does not function alone.


The Role of a Ryanodine-Sensitive Ca2+-Store in the Regulation of Smooth Muscle Tone of the Cat Gastric Fundus
Evidence is provided for the role of Ca 2+ release from a SR ryanodine-sensitive Ca2+ store in the maintenance of the muscle tone of the cat gastric fundus.
Role of sarcoplasmic reticulum in inhibitory junction potentials and hyperpolarizations by nitric oxide donors in opossum oesophagus
Results support the hypothesis that subplasmalemmal Cai2+ elevation, via vectorial Ca2+ release from superficial SR toward the plas malemma, may be an important mechanism by which NO, from NO‐liberating compounds or released from inhibitory neurones induces relaxation and in opossum oesophagus.
Cyclic GMP-induced activation of potassium currents by sarcoplasmic reticulum Ca2+ pump-dependent mechanism.
The authors' data suggest that, in gastric fundus smooth muscles, NO-liberating substances and cGMP analogues contribute to the activation of a Ca2+ -release mechanism from the cell bulk, i.e. the myoplasm surrounding the contractile filaments, towards the plasma membrane, crossing the SR Ca2-stores.
Putative, selective inhibitors of sarcoplasmic reticulum Ca+(+)-pump ATPase inhibit relaxation by nitroglycerin and atrial natriuretic factor of the rabbit aorta contracted by phenylephrine.
Results indicate that the proper functioning of SR Ca+(+)-pump ATPase is necessary for elicitation of relaxation by NTG and ANF and Enhanced sequestration of Ca++ by SR may be an important mechanism by which these compounds induce relaxation in this type of smooth muscle.
Activation of distinct cAMP- and cGMP-dependent pathways by relaxant agents in isolated gastric muscle cells.
The mechanism of action of vasoactive intestinal peptide was examined in isolated gastric and taenia coli muscle cells and compared with that of nitric oxide, sodium nitroprusside, and isoproterenol to conclude that cAK and cGK can be activated separately and mediate relaxation independently.
Effect of nitroglycerin and long‐term electrical stimulation on nitrergic relaxation in the pig gastric fundus
It is illustrated that nitroglycerin can induce a postjunctional tolerance to nitrergic stimuli in the pig gastric fundus but evidence for a preJunctional inhibition of neuronal NO synthase by NO was not obtained.