Applicability of reverse microdialysis in pharmacological and toxicological studies

Höcht, Christián; Opezzo, Javier A.W.; Taira, Carlos A.

doi:10.1016/j.vascn.2006.02.007

Cited by 44 publications

(26 citation statements)

References 93 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As a result, microdialysis has been commonly used in pharmacological and toxicological studies, in which high temporal resolution is generally not necessary. 45 Faster Online Microdialysis for Serotonin (and Dopamine). By optimizing analysis conditions, we have reduced our detection threshold for serotonin from ∼5 32,34 to 0.8 fmol ( Figure 1A,B).…”

Section: ■ Results and Discussionmentioning

confidence: 99%

Physiologically Relevant Changes in Serotonin Resolved by Fast Microdialysis

Yang

Thompson²,

McIntosh³

et al. 2013

ACS Chem. Neurosci.

View full text Add to dashboard Cite

Online microdialysis is a sampling and detection method that enables continuous interrogation of extracellular molecules in freely moving subjects under behaviorally relevant conditions. A majority of recent publications using brain microdialysis in rodents report sample collection times of 20−30 min. These long sampling times are due, in part, to limitations in the detection sensitivity of high performance liquid chromatography (HPLC). By optimizing separation and detection conditions, we decreased the retention time of serotonin to 2.5 min and the detection threshold to 0.8 fmol. Sampling times were consequently reduced from 20 to 3 min per sample for online detection of serotonin (and dopamine) in brain dialysates using a commercial HPLC system. We developed a strategy to collect and to analyze dialysate samples continuously from two animals in tandem using the same instrument. Improvements in temporal resolution enabled elucidation of rapid changes in extracellular serotonin levels associated with mild stress and circadian rhythms. These dynamics would be difficult or impossible to differentiate using conventional microdialysis sampling rates.

show abstract

Section: ■ Results and Discussionmentioning

confidence: 99%

Physiologically Relevant Changes in Serotonin Resolved by Fast Microdialysis

Yang

Thompson²,

McIntosh³

et al. 2013

ACS Chem. Neurosci.

View full text Add to dashboard Cite

show abstract

“…In addition, the drug delivered through microdialysis probe does not diffuse more than 1 mm from the probe membrane (Hocht et al, 2007;Westerink and De Vries, 2001). One limitations associated with reverse microdialysis is that the brain concentration of the delivered drug needs to be estimated from in vitro probe experiments.…”

Section: Discussionmentioning

confidence: 99%

Effect of microdialysis perfusion of 4,5,6,7-tetrahydroisoxazolo-[5,4-c]pyridine-3-ol in the perifornical hypothalamus on sleep–wakefulness: Role of δ-subunit containing extrasynaptic GABAA receptors

2008

View full text Add to dashboard Cite

Gaboxadol or 4,5,6,7-tetrahydroisoxazolo-[5,4-c]pyridine-3-ol (THIP) is a selective agonist for the δ-subunit containing extrasynaptic GABA A receptors that will soon enter the U.S. market as a sleep aid (Winsky-Sommerer et al., 2007). Numerous studies have shown that systemic administration of THIP reduces wakefulness and increases sleep both in humans and rats (Lancel and Langebartels, 2000;Walsh et al., 2007). However, it is yet unclear where in the brain THIP acts to promote sleep. Since the perifornical lateral hypothalamus (PFH) contains orexin neurons and orexin neurons are critical for maintenance of arousal (McCarley, 2007), we hypothesized that THIP may act on PFH neurons to promote sleep. To test our hypothesis, we used reverse microdialysis to perfuse THIP unilaterally into the PFH and studied its effects on sleep-wakefulness during the light period in freely behaving rats. Microdialysis perfusion of THIP (100 µM) into the PFH produced a significant reduction in wakefulness with a concomitant increase in nonREM sleep as compared to ACSF perfusion. REM sleep was unaffected. This is the first study implicating the δ-subunit containing extrasynaptic GABA A receptors in PFH in control of sleep-wakefulness in freely behaving rats. KeywordsOrexin/hypocretin; perifornical hypothalamus; THIP; reverse microdialysisThe γ-aminobutyric acid (GABA) system is closely linked with the regulation of sleepwakefulness. Thus, it is not surprising that pharmacological landscape for treatment of various sleep disorders including insomnia have been dominated by agents that activate GABA A receptors . Classical synaptic GABA transmission results in phasic inhibition that is mainly mediated by γ2 subunits containing postsynaptic GABA A receptors (Rudolph and Mohler, 2006;Ebert et al., 2006;Olsen et al., 2007), In contrast, tonic inhibition is mainly mediated by δ subunit containing "extrasynaptic" GABA A receptors (Olsen et al.,Correspondence: Mahesh Thakkar, Harry Truman Memorial Veteran's Hospital, Columbia, MO., Department of Neurology, University of Missouri, 800 Hospital Drive, Columbia, MO, 65201, Ph. (573) 814 6000 ext 53697, Email: thakkarmm@health.missouri.edu. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. 2007). These "extrasynaptic" GABA A receptors have a higher affinity for GABA and slower rates of desensitization and deactivation than do the classical synaptic receptors. NIH Public AccessThe GABA A agonist THIP selectively activates extrasynaptic GABA A receptors (WinskySommerer et al., 2007). Systemic administration of THIP induces sleep in rats and humans (...

show abstract

“…Hurtado et al, 2014), and measurement of antineoplastic drug levels in the target tissue (Höcht, Opezzo, Taira, 2007). Among these applications, the assessment of in vivo skin absorption of drugs from topical and transdermal formulations has also been described (Schnetz, Fartasch, 2001;Kreilgaard, 2002;Brunner, Derendorf, 2006).…”

Section: Cutaneous Microdialysismentioning

confidence: 99%

Evaluation of skin absorption of drugs from topical and transdermal formulations

Ruela

Perissinato

Lino

et al. 2016

Braz. J. Pharm. Sci.

216

135

View full text Add to dashboard Cite

The skin barrier function has been attributed to the stratum corneum and represents a major challenge in clinical practice pertaining to cutaneous administration of drugs. Despite this, a large number of bioactive compounds have been successfully administered via cutaneous administration because of advances in the design of topical and transdermal formulations. In vitro and in vivo evaluations of these novel drug delivery systems are necessary to characterize their quality and efficacy. This review covers the most well-known methods for assessing the cutaneous absorption of drugs as an auxiliary tool for pharmaceutical formulation scientists in the design of drug delivery systems. In vitro methods as skin permeation assays using Franz-type diffusion cells, cutaneous retention and tape-stripping methods to study the cutaneous penetration of drugs, and in vivo evaluations as pre-clinical pharmacokinetic studies in animal models are discussed. Alternative approaches to cutaneous microdialysis are also covered. Recent advances in research on skin absorption of drugs and the effect of skin absorption enhancers, as investigated using confocal laser scanning microscopy, Raman confocal microscopy, and attenuated total reflectance Fourier-transform infrared spectroscopy, are reviewed. Uniterms:Skin absorption/effects/study. Skin absorption/topical formulations. Skin absorption/ transdermal formulations. Skin absorptions/enhancers. INTRODUCTIONTopical and transdermal drug delivery systems have shown significant advantages in clinical practice for drug targeting to the action site in the body; this has reduced the systemic side effects. The administration of drugs by through the skin is also performed to achieve controlled or prolonged drug delivery, and this route can be explored as an alternative to the oral route. The oral route shows some limitations for drugs with irregular absorption in the gastrointestinal tract and low bioavailability and for drugs with increased first pass metabolism and short plasma halflife times (Barry, 2001;Wokovich et al., 2006;Prausnitz, Langer, 2009;Alexander et al., 2012).Many drug products applied to the skin surface may penetrate to some extent into the skin layers, where their effects are expected. This is the case for topical formulations for treatment of skin disorders such as acne and cutaneous inflammatory diseases that include dermatitis, erythematous lupus, and psoriasis. On the other hand, transdermal formulations release drugs that permeate through the skin and enter the systemic circulation. Transdermal therapy must ensure that significant concentrations of the drug are absorbed to reach effective plasma concentrations. Permeation of drugs is targeted in some cases to body regions close to the action site, where a regional effect is expected, e.g., in the muscles, blood vessels, and articulations. In this way, the term "cutaneous absorption" is properly used to characterize the sum of the amounts of drug that penetrate and permeate the skin (Barry, 2001;El Maghraby, Barry;Willi...

show abstract

Applicability of reverse microdialysis in pharmacological and toxicological studies

Cited by 44 publications

References 93 publications

Physiologically Relevant Changes in Serotonin Resolved by Fast Microdialysis

Physiologically Relevant Changes in Serotonin Resolved by Fast Microdialysis

Effect of microdialysis perfusion of 4,5,6,7-tetrahydroisoxazolo-[5,4-c]pyridine-3-ol in the perifornical hypothalamus on sleep–wakefulness: Role of δ-subunit containing extrasynaptic GABAA receptors

Evaluation of skin absorption of drugs from topical and transdermal formulations

Contact Info

Product

Resources

About