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PathWhiz ID Pathway Meta Data

PW147099

Pw147099 View Pathway
drug action

Trazodone H1 Antihistamine Neurological Sleep Action Pathway

Homo sapiens
Trazodone is an ethanolamine class H1 antihistamine used to treat insomnia and allergy symptoms such as hay fever and hives. It is also used with pyridoxine in the treatment of nausea and vomiting in pregnancy. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Wakefulness is regulated by histamine in the tuberomammillary nucleus, a part of the hypothalamus. Histidine is decarboxylated into histamine in the neuron. Histamine is transported into synaptic vesicles by a monoamine transporter then released into the synapse. Normally histamine would activate the H1 histamine receptor on the post-synaptic neuron in the tuberomammillary nucleus. Trazodone inhibits the H1 histamine receptor, preventing the depolarization of the post-synaptic neuron. This prevents the wakefulness signal from being sent to the major areas of the brain, causing sleepiness.

PW176645

Pw176645 View Pathway
drug action

Trazodone H1 Antihistamine Smooth Muscle Relaxation Action Pathway

Homo sapiens
Trazodone is a drug that sometimes acts as a H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. H1-antihistamines act on H1 receptors in T-cells to inhibit the immune response, in blood vessels to constrict dilated blood vessels, and in smooth muscles of lungs and intestines to relax those muscles. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. H1-antihistamines act on H1 receptors in T-cells to inhibit the immune response, in blood vessels to constrict dilated blood vessels, and in smooth muscles of lungs and intestines to relax those muscles. Allergies causes blood vessel dilation which causes swelling (edema) and fluid leakage. Trazodone also inhibits the H1 histamine receptor on bronchiole smooth muscle myocytes. This normally activates the Gq signalling cascade which activates phospholipase C which catalyzes the production of Inositol 1,4,5-trisphosphate (IP3) and Diacylglycerol (DAG). Because of the inhibition, IP3 doesn't activate the release of calcium from the sarcoplasmic reticulum, and DAG doesn't activate the release of calcium into the cytosol of the endothelial cell. This causes a low concentration of calcium in the cytosol, and it, therefore, cannot bind to calmodulin.Calcium bound calmodulin is required for the activation of myosin light chain kinase. This prevents the phosphorylation of myosin light chain 3, causing an accumulation of myosin light chain 3. This causes muscle relaxation, opening up the bronchioles in the lungs, making breathing easier.

PW176738

Pw176738 View Pathway
drug action

Trazodone H1-Antihistamine Blood Vessel Constriction Action Pathway

Homo sapiens
Trazodone is a drug that sometimes acts as a H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. H1-antihistamines act on H1 receptors in T-cells to inhibit the immune response, in blood vessels to constrict dilated blood vessels, and in smooth muscles of lungs and intestines to relax those muscles. Allergies causes blood vessel dilation which causes swelling (edema) and fluid leakage. Trazodone inhibits the H1 histamine receptor on blood vessel endothelial cells. This normally activates the Gq signalling cascade which activates phospholipase C which catalyzes the production of Inositol 1,4,5-trisphosphate (IP3) and Diacylglycerol (DAG). Because of the inhibition, IP3 doesn't activate the release of calcium from the sarcoplasmic reticulum, and DAG doesn't activate the release of calcium into the cytosol of the endothelial cell. This causes a low concentration of calcium in the cytosol, and it, therefore, cannot bind to calmodulin. Calcium bound calmodulin is required for the activation of the calmodulin-binding domain of nitric oxide synthase. The inhibition of nitric oxide synthesis prevents the activation of myosin light chain phosphatase. This causes an accumulation of myosin light chain-phosphate which causes the muscle to contract and the blood vessel to constrict, decreasing the swelling and fluid leakage from the blood vessels caused by allergens.

PW176830

Pw176830 View Pathway
drug action

Trazodone H1-Antihistamine Immune Response Action Pathway

Homo sapiens
Trazodone is a drug that sometimes acts as a H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. H1-antihistamines act on H1 receptors in T-cells to inhibit the immune response, in blood vessels to constrict dilated blood vessels, and in smooth muscles of lungs and intestines to relax those muscles. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release. First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia). Second-generation antihistamines are more selective for H1-receptors of the peripheral nervous system (PNS) and do not cross the blood-brain barrier. Consequently, these newer drugs elicit fewer adverse drug reactions.

PW127996

Pw127996 View Pathway
drug action

Trazodone mechanism of Action Action Pathway

Homo sapiens
Trazodone is triazolopyridine derivative from the serotonin receptor antagonists and reuptake inhibitors (SARIs) class of antidepressants with comparable efficacy to other drugs such as tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), and serotonin-norepinephrine receptor inhibitor (SNRIs) in the treatment of depression. A unique feature of this drug is that it does not promote the anxiety symptoms, sexual symptoms, or insomnia, which are commonly associated with SSRI and SNRI therapy. Trazodone inhibits the reuptake of serotonin and block both histamine and alpha-1-adrenergic receptors. Other mechanisms that may occur include antagonism at serotonin 5-HT1a, 5-HT1c, and 5-HT2 receptor subtypes.

PW012871

Pw012871 View Pathway
metabolic

Trehalose

Homo sapiens

PW002088

Pw002088 View Pathway
metabolic

Trehalose Biosynthesis I

Escherichia coli
Trehalose is a disaccharide made of two glucose molecules that can be used as a store of energy, as well as water retention and protection from freezing at low temperatures. In this pathway, glucose-6-phosphate from the galactose metabolism pathway combines with uridine diphosphate glucose to form alpha,alpha-trehalose 6-phosphate, as well as uridine 5’-diphosphate and a hydrogen ion as byroducts in a reaction catalyzed by alpha,alpha-trehalose-phosphate synthase [UDP-forming]. Following this, alpha,alpha-trehalose 6-phosphate is converted to alpha,alpha-trehalose following the hydrolytic cleavage of its phosphate group by trehalose-phosphate phosphatase. Alpha,alpha-trehalose can then function as energy stores until it is broken down as a part of the trehalose degradation pathway when needed.

PW123560

Pw123560 View Pathway
metabolic

Trehalose Biosynthesis I

Pseudomonas aeruginosa
Trehalose is a disaccharide made of two glucose molecules that can be used as a store of energy, as well as water retention and protection from freezing at low temperatures. In this pathway, glucose-6-phosphate from the galactose metabolism pathway combines with uridine diphosphate glucose to form alpha,alpha-trehalose 6-phosphate, as well as uridine 5’-diphosphate and a hydrogen ion as byroducts in a reaction catalyzed by alpha,alpha-trehalose-phosphate synthase [UDP-forming]. Following this, alpha,alpha-trehalose 6-phosphate is converted to alpha,alpha-trehalose following the hydrolytic cleavage of its phosphate group by trehalose-phosphate phosphatase. Alpha,alpha-trehalose can then function as energy stores until it is broken down as a part of the trehalose degradation pathway when needed.

PW088282

Pw088282 View Pathway
metabolic

Trehalose Degradation

Bos taurus
Trehalose, also known as mycose or tremalose, is a sugar consisting of two 1-1 alpha bonded glucose molecules. It is produced by some plants, bacteria, fungi and invertebrates, and can be used as a source of energy, such as for flight in insects, and as a survival mechanism to avoid freezing and dehydration. After ingestion in the intestine lumen, trehalose can interact with trehalase, which exists in the brush border of the cells there. In a reaction that also requires a water molecule, it is broken. These are then transported into the epithelial cells along with a sodium ion by a sodium/glucose cotransporter, which can bring glucose up its gradient along with sodium moving down its gradient. Once inside the cell, the glucose can then be transported out of the basolateral membrane by a solute carrier family 2 facilitated glucose transporter. From there, the glucose enters the blood stream, and is transported to liver hepatocytes. Once in the liver, glucokinase can use the energy and phosphate from a molecule of ATP to form glucose-6-phosphate, which then goes on to start the process of glycolysis.

PW064664

Pw064664 View Pathway
metabolic

Trehalose Degradation

Mus musculus
Trehalose, also known as mycose or tremalose, is a sugar consisting of two 1-1 alpha bonded glucose molecules. It is produced by some plants, bacteria, fungi and invertebrates, and can be used as a source of energy, such as for flight in insects, and as a survival mechanism to avoid freezing and dehydration. After ingestion in the intestine lumen, trehalose can interact with trehalase, which exists in the brush border of the cells there. In a reaction that also requires a water molecule, it is broken. These are then transported into the epithelial cells along with a sodium ion by a sodium/glucose cotransporter, which can bring glucose up its gradient along with sodium moving down its gradient. Once inside the cell, the glucose can then be transported out of the basolateral membrane by a solute carrier family 2 facilitated glucose transporter. From there, the glucose enters the blood stream, and is transported to liver hepatocytes. Once in the liver, glucokinase can use the energy and phosphate from a molecule of ATP to form glucose-6-phosphate, which then goes on to start the process of glycolysis.