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Effects Of Melatonin On Heartbeat And Possible Identification Of A Melatonin Receptor In Drosophila Melanogaster, Tricia L. Vankirk

Electronic Theses and Dissertations

Chapter 1 of this manuscript is a literature review that serves as an introduction to the entire dissertation. Chapter 2 examines the effects of the melatonin injection on heart rate and rhythmicity in Drosophila melanogaster Canton-S (wild-type) pupae and pupae bearing a variety of heart mutations. Chapter 3 investigates further the possible mechanisms of melatonin’s ability to increase heart rhythmicity without significantly affecting heart rate. A melatonin antagonist, luzindole; a high-affinity melatonin agonist, 2-iodomelatonin and RNAi techniques are used to identify a possible melatonin receptor in Drosophila melanogaster.

An appendix contains a previously published manuscript detailing experiments performed at the …

Monitoring Salivary Melatonin Concentrations In Children With Sleep Disorders Using Liquid Chromatography-Tandem Mass Spectrometry, Sohil Khan, Rani George, Bruce Charles, Paul Taylor, Helen Heussler, David Cooper, Treasure Mcguire, David Pache, Ross Norris

Treasure McGuire

Background; Melatonin is S5Tithesized in the pineal gland and is an important circadian phase marker, especially in the detennination of sleep patterns. Both temporary and pennanent abnormal sleep patterns occur in children; therefore, it is desirable to have methods for monitoring melatonin in biological fluids in the diagnosis and treatment of such disorders. Objective: The objective of the study is to develop a liquid chromatography-tandem mass spectrometry method for the detenni¬ nation of melatonin in saliva and to apply it to monitoring salivary concentrations in children with sleep disorders. Methods: A deuterated internal standard (dy-melatonin) was added to a diluted …

Short-Wavelength Enrichment Of Polychromatic Light Enhances Human Melatonin Suppression Potency., George Brainard, John P. Hanifin, Benjamin Warfield, Marielle K. Stone, Mary E. James, Melissa Ayers, Alan Kubey, Brenda Byrne, Mark Rollag

Department of Neurology Faculty Papers

The basic goal of this research is to determine the best combination of light wavelengths for use as a lighting countermeasure for circadian and sleep disruption during space exploration, as well as for individuals living on Earth. Action spectra employing monochromatic light and selected monochromatic wavelength comparisons have shown that short-wavelength visible light in the blue-appearing portion of the spectrum is most potent for neuroendocrine, circadian, and neurobehavioral regulation. The studies presented here tested the hypothesis that broad spectrum, polychromatic fluorescent light enriched in the short-wavelength portion of the visible spectrum is more potent for pineal melatonin suppression in healthy …

Beneficial Effects Of Melatonin And Bq-123 On The Rat Testis Damage Caused By Cigarette Smoke, Hüseyi̇n Aslan, Hakan Kesi̇ci̇, Zafer İsmai̇l Karaca, Bi̇rsen Özyurt, Ufuk Taş, Fati̇h Eki̇ci̇, Hasan Erdoğan, Fi̇kret Gevrek, Sevi̇l Çayli

Turkish Journal of Medical Sciences

Several studies have demonstrated that cigarette smoke has detrimental effects on testicular function. However, it is unknown whether melatonin or BQ-123 has beneficial effects on the rat testis damage caused by cigarette smoke. The aim of the present study was to investigate the beneficial effects of melatonin or BQ-123 on the testicular damage caused by cigarette smoke. Materials and methods: Twenty Wistar rats were randomly divided into 4 equal groups: control group (n = 5), cigarette smoke group (n = 5), melatonin group (n = 5), and BQ-123 group (n = 5). At the end of 4 weeks, all the …

Effects Of Melatonin And Theanine Administration On Pentylenetetrazole-Inducedseizures And Brain Tissue Oxidative Damage In Ovariectomized Rats, Shadi Choopankareh, Farzaneh Vafaee, Mohammad Naser Shafei, Hamid Reza Sadeghnia, Reza Salarinia, Leila Zarepoor, Mahmoud Hosseini

Turkish Journal of Medical Sciences

Background/aim: The effects of coadministration of melatonin and theanine (Mel/Thea) on pentylenetetrazole (PTZ)-induced seizures and brain tissue oxidative damage were investigated in ovariectomized (OVX) and sham-operated rats. Materials and methods: The rats were divided into the following groups: 1) sham, 2) ovariectomized (OVX), 3) sham-PTZ, 4) OVX-PTZ, 5) sham-Mel/Thea-PTZ, and 6) OVX-Mel/Thea-PTZ. Groups 1-4 received saline, while groups 5 and 6 received a combination of Mel/Thea for 6 weeks. All animals except for those in groups 1 and 2 received a single injection of PTZ. Results: The OVX-PTZ group had higher generalized tonic-clonic seizure (GTCS) latency compared to the sham-PTZ …

Plasma 8-Isopgf2? And Serum Melatonin Levels In Patients With Minimal Cognitive Impairment And Alzheimer Disease, Fevzi̇ye Burcu Şi̇ri̇n, Duygu Kumbul Doğuç, Hüseyi̇n Vural, İbrahi̇m Eren, İkbal İnanli, Recep Sütcü, Namik Deli̇baş

Turkish Journal of Medical Sciences

Background/aim: F2α-isoprostane is accepted as an oxidative stress indicator and melatonin shows neuroprotective effects by antioxidative and antiamyloidogenic influences. By measuring these in patients diagnosed with minimal cognitive impairment (MCI) and Alzheimer-type dementia, we intended to demonstrate whether the measurement of these markers contributes to early diagnosis of Alzheimer disease (AD) in the MCI stage or not. Materials and methods: Three groups (n = 63) were created: the AD group, MCI group, and control group. Serum melatonin levels were measured by radioimmunoassay method, and plasma total 8-isoPGF2α levels were measured by enzyme immunoassay method. Results: Significant differences were observed in …

G Protein-Coupled Inwardly-Rectifying Potassium (Girk) Chanels Mediate Entrainment Of Circadian Rhythms, Lauren Marie Hablitz

All ETDs from UAB

Circadian rhythms are 24-hour cycles in biological and behavioral processes. These cycles enable an organism to predict changes in its environment, like changes in food availability and seasonality. Although endogenously driven, these rhythms can entrain or synchronize to daily changes in the environment, allowing the animal to adapt. One way entrainment occurs is shifts in circadian phase following the presentation of nonphotic, or non-light, stimuli, such as exercise, arousal, or stress at certain times of day. The molecular mechanisms underlying nonphotic entrainment are poorly understood - specifically, how nonphotic cues alter excitability within the suprachiasmatic nucleus (SCN) of the hypothalamus, …

Strategies For Preventing Age And Neurodegenerative Disease-Associated Mitochondrial Dysfunction, Vedad Delic

USF Tampa Graduate Theses and Dissertations

Mitochondrial dysfunction plays a pivotal role in the development of aging phenotypes and aging-associated neurodegenerative disorders, such as Alzheimer’s disease (AD), Parkinson’s disease (PD) and Amyotrophic lateral sclerosis (ALS). Strategies that restore mitochondrial dysfunction may rescue the deficits of central metabolism in these disorders and improve cell survival. For example, we found that modulating the mTOR signaling pathway in a tissue culture model of aging-induced mitochondrial DNA mutation enhanced mitochondrial function as evidenced by increased oxygen consumption. Our previous melatonin studies also led us to hypothesize that caloric restriction and the hormone melatonin would reverse brain mitochondrial dysfunction in animal …