Search results
Results From The WOW.Com Content Network
Adenosine is a key factor in regulating the body's sleep-wake cycle. [39] Adenosine levels rise during periods of wakefulness and lowers during sleep. Higher adenosine levels correlate with a stronger feeling of sleepiness , also known as sleep drive or sleep pressure. [ 40 ]
Fatigue and sedation after heavy exertion can be caused by excess adenosine in the cells which signals muscle fiber to feel fatigued. In the brain, excess adenosine decreases alertness and causes sleepiness. In this way, adenosine may play a role in fatigue from MADD. [4] Recovery from over-exertion can be hours, days or even months.
Caffeine keeps you awake by blocking adenosine receptors. Each type of adenosine receptor has different functions, although with some overlap. [3] For instance, both A 1 receptors and A 2A play roles in the heart, regulating myocardial oxygen consumption and coronary blood flow, while the A 2A receptor also has broader anti-inflammatory effects throughout the body. [4]
A 1 receptors are implicated in sleep promotion by inhibiting wake-promoting cholinergic neurons in the basal forebrain. [6] A 1 receptors are also present in smooth muscle throughout the vascular system. [7] The adenosine A 1 receptor has been found to be ubiquitous throughout the entire body. [citation needed]
Adenosine deaminase (also known as adenosine aminohydrolase, or ADA) is an enzyme (EC 3.5.4.4) involved in purine metabolism. It is needed for the breakdown of adenosine from food and for the turnover of nucleic acids in tissues. Its primary function in humans is the development and maintenance of the immune system. [5]
The pathophysiology of cancer-related fatigue is poorly understood. It may be caused by the cancer or the effects it has on the body, by the body's response to the cancer, or by the cancer treatments. Fatigue is a common symptom of cancer. [3] Some fatigue is caused by cancer treatments. This may show a characteristic pattern.
For premium support please call: 800-290-4726 more ways to reach us
Moderate physical dependence often arises from prolonged long-term caffeine use. [4] In the human body, caffeine blocks adenosine receptors A 1 and A 2A. [5] Adenosine is a by-product of cellular activity: the stimulation of adenosine receptors produces feelings of tiredness and a drive for sleep.