Sleep is regulated by the Superchiasmatic Nucleus (SCN). The SCN coordinates the bodies sleeping habits based on external environments. However, there are subsidiary regulating factors that also help the SCN regulate sleep. One of these factors is called the Histadine Decarboxylase enzyme (HDC). HDC regulates the release of Histamine a biochemical used to induce vigilance and prevent sleep. [1] Levels of sleep consistencies can be measured by the amount of Rapid-Eye Movement (REM) phases entered in one sleeping cycle. Therefore, by decreasing the level of activation of HDC will result in an increase of REM phases in one sleep cycle duration.
The model system used in this experiment is mice. A pharmacological approach will be taken to test
this experiment. There will be two sample groups of mice, and each group would have a sample size of 35 mice. One sample group will be the control, mice with the standard HDC enzyme. The other group will have a mutated down-regulated HDC enzyme. Normal diets will be provided for both groups to avoid confounding variables. Several assays will be used in this experiment to measure how levels of HDC activation would impact the number of REM phases during the duration of one sleep cycle. The first assay used will be an Enzyme Assay. This assay is used to monitor levels of enzyme kinetics and inhibitory effects. Selection of an irreversible antagonist to the HDC enzyme is vital in insuring that inactivation of the HDC enzyme follows all the way through rather than stopping at a threshold. Application of optical nanosensors are first used to identify the amount of Histamine produced in the mice. These nanosensors recognize and bind to the chemical of interest, in this case Histamine, and emit a fluorescent light. [2] Then the chosen mutant mice will be injected with the inhibitory drug. After a duration of six hours, both the control and mutant mice will begin to be monitored by an electroencephalogram (EEG) for another 24 hours. 24 hours in this experiment will be considered the standard for one sleep cycle duration. Afterwards, wavelengths on the EEG will be analyzed and the amounts of REM phases will be identified. [3] The quantity of REM cycles should have increased in the mutant mice in comparison to the control ones because histamine is inactivated. A knockout assay can also be done to ensure that the previous experimental results were valid. In this experiment two groups were also selected. A WT control group of mice and a group of mice with the HDC enzyme selectively knocked out. The HDC knocked out mice were chosen from the C57BL/6j strain. Like the previous experiment the knockout assay undergoes a 24-hour sleep cycle that is comprised of 12 light hours. An EEG is also applied to the mice to monitor sleep and wakefulness levels after one standard period. [4] REM phase frequencies will also be identified from both the wild-type and knockout mice. The knockout mice should show a higher frequency of REM sleep compared to the Wild-Type mice in a 24-hour interval. These experiment is used to show how down-regulation of the HDC enzyme would increase the activity of REM phases during a 24-hour sleeping period. Complete inhibition of the enzyme would lead to higher sleep consistency and lower states of vigilance.
In this experiment mice were studied as examples of organisms that employ physiological mechanisms to maintain and regulate internal body temperature.
“Animals of different ages, sexes, developmental stages, and of different health status can all respond differently to experimental treatments. It is no surprise, then, that humans respond differently to administered pharmaceuticals than other animals” (Physicians Committee for Responsible Medicine).Thalidomide being the most well known example was a drug sold between 1957 and 1961 and was marketed towards pregnant women and was said to relieve morning sickness, stress and to help them sleep. The drug was tested thoroughly on mice, with no ill eff...
Most of the research in the literature is quantitative, a significant amount of which is biomedical. A common approach is animal studies which are limited in what they can tell us about the human condition. Rat models a...
“An Examination of Animal Experiments.” Physician Committee for Responsible Medicine. N.p., n.d. Web. 13 Feb. 2014. .
We live our entire life in two states, sleep and awake1. These two states are characterized by two distinct behaviors. For instance, the brain demonstrates a well-defined activity during non-REM sleep (nREM) that is different when we are awake. In the study of sleep by Huber et. al., the authors stated that sleep is in fact a global state2. It is unclear whether this statement means that sleep is a state of global behavioural inactivity or the state of the global nervous system. The notion that sleep is a global state of the nervous system served as basis for sleep researchers to search for a sleep switch. The discovery of the sleep switch, in return, provided evidence and enhanced the notion that sleep is a global state of the nervous system. The switch hypothesis developed from the fact that sleep can be initiated without fatigue and it is reversible1. It was hypothesized that there is something in the brain that has the ability to control the whole brain and initiate sleep. Studies have found a good candidate that demonstrated this ability3. They found a group of neurons in the Ventrolateral Preoptic (VLPO) nucleus. It was a good candidate because it was active during sleep, has neuronal output that can influence the wakefulness pathway, and lesion in the area followed reduce sleep3. The idea that there is something that can control the whole brain and result sleep state supports the idea that sleep is a global state of the nervous system.
In 1953, Professor Nathaniel Kleitman and Eugene Aserinsky closely observed a stage of sleep that they called Rapid Eye Movement (REM). They used an electrooculogram, which they taped to the patient’s eyelids and it recorded eye movement which became rapid during REM sleep. They also used an electromyography to measure movements of the chin and neck during sleep. Surprisingly, they found that there was little movement in the chin and neck region, which is still...
studying the subject, the origins in the brain responsible for sleep are still not fully understood and thus, facilitate continual probes
Sleepiness, whether due to sleep apnea, heavy snoring, idiopathic hypersomnolence, narcolepsy or insomnia from any number of sleep-related disorders, threatens millions of Americans' health and economic security (1). Perhaps somewhat most concerning of these disorders are those that allow sleep without having any control over when it happens-idiopathic hypersomnolence and narcolepsy. The two are closely related in that both cause individuals to fall asleep without such control, yet narcolepsy occurs without any dreaming during naps (2). For years, narcoleptic people have been falling asleep in corners, concerned, as they have given numerous attempts to try to stay focused and awake. But besides the excessive fatigue that people experience, there surely must be more that can be associated with causing such sleepiness among people at an uncontrolled level. There might especially not be a reason involving the I-function of the brain, as people are not aware of when necessarily they will fall into their deep sleep.
Kales, A. (1972). The evaluation and treatment of sleep disorders : Pharmacological and psychological studies. In M. Chase (ed.)The Sleeping Brain. Los Angeles : Brain Information Service.
Biomedical Research | Animal Use Research. N.p., n.d. Web. The Web. The Web. 19 Apr. 2014.
Sleeping is something that is an essential part of human nature and is a must in order for one to be a functional human being. Sleep is an idea that is accompanied by many wives’ tales, including the idea that one needs seven to eight hours of sleep each night and alcohol helps one fall asleep and sleep more soundly. One myth about sleep is that during sleep, one is in a state of nothingness. In truth, however, it has been discovered that during sleep the brain is active, variations in heartbeat and breathing occur, and the eyes and ears are active throughout the time of sleep. These activities during a person’s sleep are important because they help that person be more aware, awake, and alert during sleep.
Have you ever stayed up too late? At one time or another most people have probably experienced that feeling where their eyes start to droop and blur. It’s their body telling them they need to sleep… But do they? Many people might think losing a night’s sleep or not sleeping enough is not a big deal, but in fact, continuously lacking sleep does affect people in a bad way. People should know the healthy amount of sleep they need and some solutions to sleeping problems. Sleep deprivation causes physical and mental effects on the human body and can be directly responsible for many fatal accidents.
Sleep disorders are an underestimated public health concern considering that fifty to seventy million Americans are affected. Technological advances in the field of sleep have facilitated various theories to explain the need for and the purpose of sleep. Scientist have uncovered many types of sleep disorders such as insomnia, sleep apnea, and narcolepsy. Sleep disorders affect men ,women, children, the elderly, and the obese in different ways. Factors such as the number of children and the effects of menopause have been studied to determine their effects on sleep. Various treatments have been utilized ranging from non-pharmacologic to pharmacologic methods. Scientist have pinpointed areas of the brain that are involved in sleep deprivation and hormones that ultimately affect sleep.
Sleep is a very important factor in the human function. Our body and brain is able to reset itself and rejuvenate while we sleep. When we do not get the required amount of sleep, we start to feel lethargic and foggy minded, because our mind and body wasn’t able to replenish itself. Sleep is imperative that an insignificant rest deficiency or lack of sleep can affect our ability to remember things; decisions and can affect our temperament. Chronic sleep deficiency can get the body to feel agitated and it could lead to serious health problems such as, heart problems, stress, acne, and obesity.
Another goal of behavioral pharmacology is to develop animal behavioral models to screen chemical compounds with therapeutic potentials. Scientists who are studying this field typically use small animals to study psychotherapeutic drugs such as antipsychotics, antidepressants and anxiolytics, and drugs of abuse such as nicotine, cocaine, methamphetamine. [6]