This paper reflects the research and thoughts of a student at the time the paper was written for a course at Bryn Mawr College. Like other materials on Serendip, it is not intended to be "authoritative" but rather to help others further develop their own explorations. Web links were active as of the time the paper was posted but are not updated.
Biology 202, Spring 2005
First Web Papers
Start with something you're interested in, "surf", don't be afraid to get away from your initial question. Learn something. Being left with these instructions, I began to do exactly that. What I ended up with is a list of topics, which I will bring up in our regular postings, and an interest in something that had never crossed my mind. This past weekend I decided to write my paper on the science behind tickling, and why we cannot tickle ourselves. Today, while shadowing an Obstetrician, Gynecologist, I found an article on PMS and its connection to drug withdrawal. What is usually considered a reproductive process, a monthly emotional and physical setback, is now being connected to withdrawal. According to Dr. Joseph F. Smith, drug withdrawal is a syndrome, which occurs in drug and alcohol addicted individuals who discontinue or reduce the use of their drug of choice. This process of eliminating drugs and alcohol from the body is known as detoxification. Anxiety, insomnia, perspiration, body aches, and tremors are just a few of the physical and psychological symptoms of drug and alcohol withdrawal that may occur during detoxification (1). Like me, Im sure you are all asking what drug is involved in PMS? When and how do we become addicted? Why are we lacking it every month? How does this drug and lack thereof, affect our bodies?
Many women know without even looking at the calendar that their menstrual cycle is about to begin. Common signals are breast tenderness, a feeling of bloatedness or weight gain, feeling tired or "down" or more irritable (2). These changes are entirely normal. But for a small proportion of women there are emotional and behavioral symptoms that are more severe. They affect the way they do their jobs, their relationships with others, or the way they see themselves. It is not normal when premenstrual symptoms interfere with women's lives. These symptoms are a result of Premenstrual Syndrome (PMS).
PMS is a cluster of emotional, behavioral and physical symptoms that have a cyclic pattern related to the menstrual cycle. They usually occur in the week or two weeks before a woman's period. In severe cases, the predominant symptoms are likely to include at least five of the following symptoms: irritability or persistent anger; tension, headaches, anxiety; feeling depressed, upset stomach, bloatedness, joint or muscle pain, mood swings; difficulty concentrating; food cravings or changes in appetite; fatigue, lack of energy; sleep problems; physical symptoms such as breast tenderness, swelling, and aches. The causes of PMS are not yet clear but researchers believe that some women may be more sensitive than others to changing hormone levels during the menstrual cycle.
Recent research studies suggest that PMS may be caused by something similar to drug withdrawal-in this case, the woman's own hormones (3). Hormones are the chemicals "messengers" that, in concert with the nervous system, coordinate the activities of billions of cells in the human body- in this case, menstruation. Throughout this discourse, the drug, so to speak, is a woman's own hormones. Research is being done at Allegheny University that tests the effects of progesterone in the body during menstruation (4). Progesterone is a hormone prevalent in the menstrual cycle and during pregnancy. Progesterone levels are elevated in the second half of the menstrual cycle, and drops to very low levels right before the premenstrual period. The problem with hormones during menstruation occurs when progesterone is converted into another hormone called allopregnanolone, which acts like a sedative, or valium, or even alcohol. This hormone can make you feel relaxed, reduce anxiety, and even reduces seizures. Its effects are to increase the effectiveness of a transmitter in the brain called GABA (Gamma amino buteric acid). GABA is a key transmitter in the nervous system, acting almost like a "plug and socket" between the nerves that communicate in drug use, its receptors are found all over the brain (5). These are the drugs that our body is "begging" for during PMS. Allopregnanolone is like the other drugs (valium, alcohol) in terms of acting as the GABA receptor. So basically, high doses of progesterone and allopregnanolene cause less anxiety and other symptoms of PMS.
As I mentioned before, withdrawal occurs after the drug is discontinued (low levels of allopregnanolone). Although PMS is more subtle, the symptoms are similar to actual "drug" addicts, even women who are epileptic report more seizures during the premenstrual period. Drugs affect mood by altering brain chemistry, specifically the production of neurotransmitters. Neurotransmitters enable nerve impulses to travel through the CNS and regulate thought process, behavior, and emotion. Allopregnanolone acts like a depressant, decreasing neurotransmitter levels. When drug consumption becomes regular, the body adjusts to its constant presence by changing its normal production of neurotransmitters. If the usage suddenly stops or decreases the body and the CNS react to the normal dosage's absence with the symptoms that I have already mentioned.
One study was done on rats that were given progesterone for three weeks and then suddenly discontinued (4). The rats became more anxious; seizures were more easily induced in these rats than the rats that were not given progesterone. The rats were going through withdrawal. When the scientist looked at the actual brain cells, they found that GABA was less effective in calming brain cells after withdrawal from the hormone. GABA normally acts to calm brain cells, so maybe the nerve cells were more excitable, thus leading to the behavioral changes like anxiety, aggression or irritability.
The research being done on PMS has major implications for the future of women. The symptoms of PMS can make a woman's week absolutely miserable, and will not only affect her, but everyone around her. The results of the aforementioned study led to the discovery of a substance that can prevent receptor abnormality thus decreasing the behavioral effects of progesterone and allopregnanolone withdrawal. Even though this drug was rat specific, I am sure that they will be able to find the humans equivalent, and prevent some of the undesirable symptoms associated with PMS. In the meantime, I do not understand why increased levels of progesterone and allopregnanolone are not administered to PMS sufferers. Throughout my research, I did not find any articles suggesting that solution. My suggestion would be to administer some kind of pill containing higher levels of progesterone for women to take during their menstrual cycle. Other studies have been done questioning the causes of PMS. One study conducted by David Rubinow and Peter Schmidt was done at the NIMH in 1998 (6). They found that hormones alone were not the cause of premenstrual symptoms. Another study was done concluding that calcium deficiencies were the cause of the premenstrual symptoms (6). Clearly, the exact causes of PMS remains a mystery. At the beginning of my research I thought PMS was routine, that everyone suffered from mild cramps and had cravings. I assumed it was a regular part of the menstrual cycle. Now, coming to the end of my paper I realized that there are so many more factors involved. Physiological, biological, neural, emotional, behavioral, and societal factors are the most prevalent. This leads me to raise more questions. Can theories of "mind over matter" be included in this discussion? The power of the mind and its effect on behavior does play a role. How can the symptoms be measured, and when does mild become severe? Young women are usually taught about the menstrual cycle before onset. They also talk amongst their peers. Many women are taught to believe that the onset of their menstrual cycles leads to pain and discomfort, many women, like myself, accept PMS as a normal reproductive/biological/physiological process. As was said in class, our minds have strong influences over our behavior.
1) Withdrawal syndromes Dr. Joseph F. Smith: Medical http://www.chclibrary.org/micromed/00070960.htmlLibrary
2)Premenstrual Syndrome National Women's Health Information Center
3)Understanding PMS-UPENN health system
4)The Health Report 1998
5)Biochemistry of Neurotransmitters
6)PMS and PMDD Cause Serious Suffering
7) Slade, P. (1984) Premenstrual emotional changes in normal women: Fact or fiction?
Journal of Psychosomatic Research, 28. 1-7.
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