What is the main mechanism of tramadol?

Tramadol is an analgesic that is used worldwide for pain, but its mechanisms of action have not been fully elucidated. The majority of studies to date have focused on activation of the μ-opioid receptor (μOR) and inhibition of monoamine reuptake as mechanisms of tramadol. Although it has been speculated that tramadol acts primarily through activation of the μOR, no evidence has revealed whether tramadol directly activates the μOR.

Kisspeptin-10 potentiates miniature excitatory postsynaptic currents in the rat supraoptic nucleus.

Kisspeptin is the natural ligand of the G protein-coupled receptor -54 and plays a major role in gonadotropin-releasing hormone secretion in the hypothalamus. Kisspeptin-10 is an endogenous derivative of kisspeptin and has 10 -amino acids. Previous studies have demonstrated that central administration of kisspeptin-10 stimulates the secretion of arginine vasopressin (AVP) in male rats.

High-frequency stimulation restored motor-evoked potentials to the baseline level in the upper extremities but not in the lower extremities under sevoflurane anesthesia in spine surgery.

Background: Volatile anesthetics attenuate medium-frequency (250 to 500 Hz) pulse train transcranial electrical stimulation (TES) motor-evoked potentials (MEPs) better than propofol. High-frequency (1000 Hz) TES may restore hand MEP amplitude under volatile anesthesia, but its effect on leg MEPs critical for spine surgery monitoring is unknown.

Methods: The effects of sevoflurane and propofol and modulation of the stimulation frequencies on MEPs elicited by TES in the anterior tibial, abductor hallucis, and abductor pollicic brevis muscles were investigated in 31 patients undergoing spine surgery.

Sevoflurane inhibits the µ-opioid receptor function expressed in Xenopus oocytes.

Sevoflurane is widely used for anesthesia, and is commonly used together with opioids in clinical practice. However, the effects of sevoflurane on μ-opioid receptor (μOR) functions is still unclear. In this study, the effects of sevoflurane on μOR functions were analyzed by using Xenopus oocytes expressing a μOR fused to chimeric Gα protein G(qi5) (μOR-G(qi5)).

Effects of sevoflurane on voltage-gated sodium channel Na(v)1.8, Na(v)1.7, and Na(v)1.4 expressed in Xenopus oocytes.

Sevoflurane is widely used as a volatile anesthetic in clinical practice. However, its mechanism is still unclear. Recently, it has been reported that voltage-gated sodium channels have important roles in anesthetic mechanisms.

The tramadol metabolite O-desmethyl tramadol inhibits substance P-receptor functions expressed in Xenopus oocytes.

Tramadol has been widely used as analgesic. O-Desmethyl tramadol (ODT) is one of the main metabolites of tramadol, having much greater analgesic potency than tramadol itself. Substance P receptors (SPR) are well known to modulate nociceptive transmission within the spinal cord.

[Screening of sleep apnea syndrome with Sleeprecorder SD-101].

Polysomnography (PSG) has been the gold standard for the diagnosis of sleep apnea syndrome (SAS). However, PSG is not generally available since it is technically demanding, and cost and labour are necessary. Currently, there is growing demand for its diagnosis.

[Anesthesia in a patient with alkaptonuric ochronosis for total hip arthroplasty].

Alkaptonuric ochronosis, caused by a deficiency of homogentisate 1,2-dioxygenase, is a rare, autosomal recessive, metabolic disorder. Accumulation of homogentisate acid (HGA) at the connective tissue destructs the spine and large joints, and cardiac valvular disease is prominent. In this report, we describe a case of alkaptonuric ochronosis for anesthetic management.

[Effects of colforsin daropate hydrochloride on myocardium, smooth muscle and renal function].

In the failing heart, numerous changes occur in cardiac adrenergic receptors (ARs) and intracellular signal transduction pathways. The most striking of these alterations appears at beta1 ARs, and the desensitization is the most prominent. Since malfunctions of beta1 ARs prevent intracellular signal transduction, the desensitization plays an important role in the onset and progression of the heart failure.

The tramadol metabolite, O-desmethyl tramadol, inhibits 5-hydroxytryptamine type 2C receptors expressed in Xenopus Oocytes.

Purpose: Tramadol is widely used clinically as an analgesic, yet the mechanism by which it produces antinociception remains unclear. O-Desmethyl tramadol, the main metabolite of tramadol, is a more potent analgesic than tramadol. We reported previously that tramadol inhibits the 5-hydroxytryptamine (5-HT) type 2C receptor (5-HT(2C)R), a G-protein-coupled receptor that is expressed widely within brain and that mediates several effects of 5-HT, including nociception, feeding, and locomotion.

Effects of anesthetics on mutant N-methyl-D-aspartate receptors expressed in Xenopus oocytes.

Alcohols, inhaled anesthetics, and some injectable anesthetics inhibit the function of N-methyl-d-aspartate (NMDA) receptors, but the mechanisms responsible for this inhibition are not fully understood. Recently, it was shown that ethanol inhibition of NMDA receptors was reduced by mutation of residues in the transmembrane (TM) segment 3 of the NR1 subunit (F639A) or in TM4 of the NR2A subunit (A825W), suggesting putative ethanol binding sites. We hypothesized that the actions of other anesthetics might also require these amino acids and evaluated the effects of anesthetics on the NMDA receptors expressed in Xenopus oocytes with two-electrode voltage-clamp recording.

[Complications related to anesthesia in the University of Occupational and Environmental Health Hospital].

Background: Complications related to anesthesia remain a problem. We studied the incidence of complications during anesthesia in 2688 patients who had undergone anesthesia in the University of Occupational and Environmental Health Hospital.

Methods: We checked the anesthesia records retrospectively and analyzed the collected data for the incidence of complications during anesthesia.

The effects of the tramadol metabolite O-desmethyl tramadol on muscarinic receptor-induced responses in Xenopus oocytes expressing cloned M1 or M3 receptors.

O-desmethyl tramadol is one of the main metabolites of tramadol. It has been widely used clinically and has analgesic activity. Muscarinic receptors are involved in neuronal functions in the brain and autonomic nervous system, and much attention has been paid to these receptors as targets for analgesic drugs in the central nervous system.

The effects of the neurosteroids: pregnenolone, progesterone and dehydroepiandrosterone on muscarinic receptor-induced responses in Xenopus oocytes expressing M1 and M3 receptors.

The neurosteroids pregnenolone, progesterone, and dehydroepiandrosterone (DHEA) occur naturally in the nervous system. They act on neural tissues, participate in neuronal signaling, and are reported to alter neuronal excitability via nongenomic mechanisms. Muscarinic receptors have important roles in neuronal functions in the brain and autonomic nervous system.

[Complications related to anesthesia method in the University of Occupational and Environmental Health Hospital].

Background: Complications related to anesthesia remain a problem. We studied the incidence of complications during anesthesia in 2758 patients who had undergone anesthesia in the University of Occupational and Environmental Health Hospital.

Methods: We checked the anesthesia records retrospectively and analyzed the collected data for the incidence of complications during anesthesia.

[The management of extirpation of chronic expanding hematoma after thoracoplasty in the chest].

A 71-year-old man was scheduled for an extirpation of chronic expanding hematoma (CEH) of his right thorax. He had a history of right thoracoplasty for tuberculosis 37 years previously. He complained of dyspnea that had deteriorated over three months.

[The airway management using laryngeal mask airway and tracheal fiberscopy in a pediatric patient with tracheal stenosis after tracheostomy].

A 9-year-old boy was scheduled for excision of tracheal granuloma which had developed at the tip of a tracheostomy tube. Instead of a tracheostomy tube, a 4 mm ID tracheal tube was inserted via the tracheostomy beyond the tracheal constriction because of rapid development of respiratory failure. General anesthesia was induced and maintained with sevoflurane and oxygen via the tube, and a size 2.

Gargling with povidone-iodine reduces the transport of bacteria during oral intubation.

Purpose: Nosocomial pneumonia remains a common complication in patients undergoing endotracheal intubation. This study examined the transport of bacteria into the trachea during endotracheal intubation, and evaluated the effects of gargling with povidone-iodine on bacterial contamination of the tip of the intubation tube.

Methods: In the gargling group, patients gargled with 25 mL of povidone-iodine (2.

Analysis of the effects of halothane on Gi-coupled muscarinic M2 receptor signaling in Xenopus oocytes using a chimeric G alpha protein.

Metabotropic G protein-coupled receptors have recently been recognized as targets for anesthetics and analgesics. In particular, G(q)-coupled receptors such as muscarinic M(1) receptors (M(1)R) and 5-hydroxytryptamine (5-HT) type 2A receptors have been reported to be targets for anesthetics. Much less is known, however, about the effects of anesthetics on G(i)-coupled receptors.

Anesthetic management of patients with severe peripheral ischemia due to calciphylaxis.

Calciphylaxis is a small-vessel disease associated with renal failure. Here, we report the management of a 43-yr-old man with calciphylaxis who received left lower leg amputation with prostaglandin E(1) (PGE(1)) under monitoring by laser Doppler blood flowmetry in the left second and third fingers. Anesthesia was induced with midazolam, fentanyl, and vecuronium and was maintained with oxygen, nitrous oxide, and sevoflurane.

Intramuscular tramadol increases gastric pH during anesthesia.

Purpose: Tramadol, [(1RS, 2RS)-2-dimethylamino) methyl-1-(3-methoxyphenyl)-cyclohexanol hydrochloride], is an analgesic in clinical use. It has been reported that tramadol inhibits muscarinic type 3 receptor function, which primarily mediates smooth muscle contraction and glandular secretion. We investigated the effects of tramadol on the pH of gastric juices during anesthesia to determine whether tramadol inhibits secretion from the gastric glands.

The inhibitory effects of tramadol on 5-hydroxytryptamine type 2C receptors expressed in Xenopus oocytes.

Unlabelled: Although tramadol is widely available as an analgesic, its mechanism of antinociception remains unresolved. Serotonin (5-hydroxytryptamine, 5-HT) is a monoaminergic neurotransmitter that modulates numerous sensory, motor, and behavioral processes. The 5-HT type 2C receptor (5-HT(2C)R) is one of the major 5-HT receptor subtypes and is implicated in many important effects of 5-HT, including pain, feeding, and locomotion.

A forskolin derivative, colforsin daropate hydrochloride, inhibits the decrease in cortical renal blood flow induced by noradrenaline or angiotensin II in anesthetized rats.

A forskolin derivative, colforsin daropate hydrochloride (CDH), acts directly on adenylate cyclase to increase the intracellular cyclic adenosine monophosphate levels which produce a positive inotropic effect and a lower blood pressure. However, little is known about the effects of CDH on the renal function. We used laser Doppler flowmetry to measure the cortical renal blood flow (RBF) in male Wistar rats given a continuous intravenous infusion of CDH and evaluated the effects of CDH on the noradrenaline (NA) and angiotensin II (AngII) induced increases in blood pressure and reductions in RBF.