Search results for "Tachyphylaxi"

The emergence of loss of efficacy during antidepressant drug treatment for major depressive disorder: An integrative review of evidence, mechanisms, …

2018

The re-emergence (i.e. ‘breakthrough’) of depressive symptoms despite maintenance treatment of depression with antidepressant drugs is a complex clinical phenomenon referred to as tolerance. Herein we critically appraise evidence from both pre-clinical and clinical studies, focusing on putative mechanisms as well as clinical correlates and implications of the emergence tolerance during antidepressant treatment for major depressive disorder (MDD). It is firstly unclear to what extent this phenotype reflects a pharmacological effect of an antidepressant, is driven by non-adherence, is a marker of latent bipolarity or another comorbidity, a marker of neuroprogression of the underlying disorder…

Local anesthetic switching for intrathecal tachyphylaxis in cancer patients with pain.

2003

IMPLICATIONS Switching from bupivacaine to lidocaine may improve intrathecal morphine analgesia in advanced cancer patients, possibly because of different spinal mechanisms limiting the hyperalgesic processes.

P105. New findings on vasodilator potency, tachyphylaxis, and bioavailability of organic nitrates reveal: The tolerance-devoid clinical action of pen…

2006

Inactivation and tachyphylaxis of heat-evoked inward currents in nociceptive primary sensory neurones of rats.

2000

In contrast to other sensory modalities, pain does not decrease when a noxious stimulus is applied at constant intensity (Greene & Hardy, 1962). From this lack of adaptation on the perceptive level it has traditionally been implied that primary nociceptive afferents also do not adapt upon constant stimulation. This is in contrast to the results of recordings from these afferents, which exhibit pronounced adaptation for physical as well as chemical stimuli (Meyer et al. 1994). Peripheral adaptation of nociceptive nerve endings is compensated by central summation (Mendell & Wall, 1965; Price et al. 1977); this slow summation process of small fibre input to the dorsal horn of the spinal cord i…

Monitoring White Blood Cell Mitochondrial Aldehyde Dehydrogenase Activity: Implications for Nitrate Therapy in Humans

2009

Recent animal data suggest that reduced lipoic acid (LA) prevents oxidative inhibition of the nitrate bioactivating enzyme, the mitochondrial aldehyde dehydrogenase (ALDH-2), and that pentaerythritol tetranitrate (PETN) does not induce nitrate tolerance because of its intrinsic antioxidative properties, thereby preserving ALDH-2 activity. We sought to determine whether ALDH-2 activity in circulating white blood cells (WBCs) can be used to monitor nitrate tolerance and whether LA can prevent nitroglycerin tachyphylaxis in humans. Eight healthy male volunteers received, in randomized order, a single dose of glyceryl trinitrate (GTN; 0.8 mg), PETN (80 mg), or GTN plus LA (600 mg) orally. GTN (…

Two types of receptors for 5-hydroxytryptamine on the cholinergic nerves of the guinea-pig myenteric plexus

1985

Abstract The effects of 5-hydroxytryptamine (5-HT) on spontaneous and electrically-evoked release of [3H]-acetylcholine (ACh) from guinea-pig myenteric plexus preparations preincubated with [3H]-choline have been investigated in the absence of cholinesterase inhibitors. 5-HT caused a transient increase in spontaneous release and an inhibition of the electrically-evoked release of [3H]-ACh. The 5-HT-induced contractions of the longitudinal muscle were clearly related to the increase in spontaneous release. The inhibitory effect was not due to activation of alpha-adrenoceptors since it was also observed in the presence of tolazoline and on strips from reserpine-pretreated guinea-pigs. After d…

Antiasthmatic effects of gamma linolenic acid -high dose Evening Primrose Oil and Borage Oil stimulate allergen tachyphylaxis of sensitized guinea pi…

2012

Summary Evening primose oil (EPO) and borage oil (BO), which contain high amounts of gamma linolenic acid (10% or 20%) and are described to stimulate prostaglandin E biosynthesis, were investigated in guinea pigs for their ability to stimulate an important active self protecting mechanism against allergens (“allergen tachyphylaxis”). Groups of 12 guinea pigs sensitized to ovalbumin were fed over five days with either EPO or BO (100mg/kg/day or 1 g/kg/day) prior to sequential allergen inhalation challenges (time 0′, 10′, 20′, 60′, 70′ and 80′). Bronchial obstruction was measured by whole body plethysmography. 100 mg/kg EPO did not alter the bronchial reactions of the animals; 100 mg and 1 g/…

Wirksamkeit und Verträglichkeit von Salmeterol in der Langzeit-therapie bei Patienten mit obstruktiver Atemwegserkrankung

2000

BACKGROUND Salmeterol is a long-acting inhaled beta 2-agonist with a bronchodilating effect lasting over 10 to 12 hours. METHODS A prospective, open, multi-centre study was performed to evaluate the efficacy and safety of inhaled salmeterol (50 micrograms BID) over a mean treatment period of 29 months (range: 4-1145 days) in 634 patients (54% male, age 45 +/- 15 years) with mild to moderate asthma or chronic obstructive pulmonary disease (COPD). Peak expiratory flow rates, rescue use of short acting beta 2-agonists and safety were study objectives. Patients were critically monitored for a possible loss of bronchodilator efficacy of salmeterol during long-term treatment. RESULTS During the f…

Characteristics of histamine tachyphylaxis in rat uterine smooth muscle.

2002

Objective and design: To study both the desensitisation induced by short-term exposure to histamine and the mechanism responsible in the isolated rat uterus.¶Material: Precontracted isolated uterus (37 mM KCl) from oestrogenised Wistar rats were used.¶Treatment: Repetitive responses to histamine (10–6, 10–5, 10–4, 10–3 M), dimaprit and clonidine (10–4 M) were tested at 15, 30, 45 and 105 min., with their modifications by (5 mg/ kg, 24 h before sacrifice) reserpine, 10–7 M propranolol, 10–8 M atropine, and 10–6 M indomethacin. Dose-response curves for adrenaline were carried out as standard protocol.¶Methods: In vitro techniques (de Jalon's solution, 31°C, carbogen, isotonic registration, re…