A5054858824- Neuroscience and Neuropharmacology Research
- Memory and Neural Mechanisms
- Neural dynamics and brain function
- Neurotransmitter Receptor Influence on Behavior
- Nicotinic Acetylcholine Receptors Study
- Receptor Mechanisms and Signaling
- Sleep and Wakefulness Research
- Olfactory and Sensory Function Studies
- Neonatal and fetal brain pathology
- Neuroendocrine regulation and behavior
- Prenatal Substance Exposure Effects
- Cholinesterase and Neurodegenerative Diseases
- Birth, Development, and Health
- Photoreceptor and optogenetics research
- Neuroinflammation and Neurodegeneration Mechanisms
- Circadian rhythm and melatonin
- Sleep and related disorders
- Stress Responses and Cortisol
- Alkaloids: synthesis and pharmacology
- Nitric Oxide and Endothelin Effects
- Medicinal Plants and Neuroprotection
- Traditional and Medicinal Uses of Annonaceae
- Neurological disorders and treatments
- Chemical synthesis and alkaloids
- Hearing, Cochlea, Tinnitus, Genetics
Queen's University
2013-2024
Western University
1992-1998
Heinrich Heine University Düsseldorf
1998
University of New Mexico
1993
University of Lethbridge
1991-1993
University of Münster
1933
Abstract Mitragynine is the major psychoactive alkaloid of plant kratom/ketum. Kratom widely used in S outheast A sia as a recreational drug, and increasingly appears pure compound or component ‘herbal high’ preparations W estern world. While mitragynine/kratom may have analgesic, muscle relaxant anti‐inflammatory effects, its addictive properties effects on cognitive performance are unknown. We isolated mitragynine from performed thorough investigation behavioural rats mice. Here we...
The discovery of long-term potentiation (LTP) provided the first, direct evidence for long-lasting synaptic plasticity in living brain. Consequently, LTP was proposed to serve as a mechanism information storage among neurons, thus providing basis behavioral and psychological phenomena learning memory formation. However, several decades, LTP-memory hypothesis remained highly controversial, with inconsistent contradictory barrier its general acceptance. This review summarizes history these...
Abstract In the hippocampus, CA1 region is selectively vulnerable to effects of chronic prenatal ethanol exposure. guinea‐pig, number pyramidal cells decreased after We tested hypotheses that exposure (through maternal ingestion) results in impairments spatial learning and short‐ long‐term plasticity postnatal guinea‐pig hippocampus. Timed, pregnant guinea‐pigs were treated with (4 g/kg body weight/day), isocaloric sucrose/pair‐feeding, or water throughout gestation. Offspring studied...
Background: Mitragynine is the major alkaloid of Mitragyna speciosa (Korth.) or Kratom, a psychoactive plant widely abused in Southeast Asia. While addictive effects substance are emerging, adverse cognitive this drug and neuropharmacological actions insufficiently understood. Aims: In present study, we investigated mitragynine on spatial learning synaptic transmission CA1 region hippocampus. Methods: Male Sprague Dawley rats received daily (for 12 days) training sessions Morris water maze,...
Acetylcholine (ACh) plays a permissive role in developmental plasticity of fibers from the lateral geniculate nucleus (LGN) to primary visual cortex (V1). These remain plastic and express long-term potentiation (LTP) adult rodents, but it is not known if ACh modulates this form mature V1. We show that, anesthetized rats, theta burst stimulation (TBS) LGN using 5 or 40 cycles produced moderate (∼20%) stronger (∼40%) potentiation, respectively, field postsynaptic potentials recorded...
Long-term potentiation (LTP) and long-term depression are thought to mediate activity-dependent brain plasticity but their role in the development of thalamocortical auditory system vivo has not been investigated. In adult urethane-anaesthetized rats, theta-burst stimulation medial geniculate nucleus produced robust LTP (40% amplitude enhancement) field post-synaptic evoked potentials recorded superficial layers primary cortex. Low-frequency (1-Hz) resulted transient ( approximately 40%)...
Hippocampal theta activity is linked to various processes, including locomotion, learning and memory, defense affect (i.e., fear anxiety). Interestingly, all classes of clinically effective anxiolytics, as well experimental compounds that decrease anxiety in pre-clinical animal models anxiety, reduce the frequency hippocampal elicited by stimulation reticular formation freely behaving or anesthetized animals. In present experiments, we found bilateral histamine infusions (0.5 µg/hemisphere)...
Hippocampal theta oscillations are linked to various processes, including locomotion, learning and memory, defense affect. The lateral septum (LS) has been implicated in the generation of hippocampal rhythm, but its precise role this process is not well understood. Here, we investigated effects direct pharmacological inhibition or disinhibition dorsal LS (dLS) on frequency activity elicited by stimulation reticular formation urethane-anesthetized rats. We found that bilateral infusions GABAA...
Abstract In two experiments the authors failed to detect an effect of inducing bilateral, long‐lasting synaptic potentiation at perforant path dentate synapses on spatial learning by rats in Morris place navigation task. Daily sessions high‐frequency stimulation axons produced large increases asymptotic level population spike and field excitatory postsynaptic potential recorded ipsilateral gyrus. Place proceeded normally 24 hours after last 14 that had previously mastered procedural aspects...
The eating behavior of rats (Rattus norvegicus) given food pellets specified size was examined as a function environmental, circadian, and experiential influences. Eating times were shorter in lighted, exposed environments than dark, covered environments, even though novel, conditions the made many scanning movements they ate. time also varied circadian cycle that night portion day-night cycle. Finally, decreased if deprived, deprivation had small but enduring influence. Within tests there...