Parkinsons Disease and Tourettes Syndrome Essay -- Biology Essays Re

Parkinson's Disease and Tourette's Syndrome Parkinson's Disease is a literally crippling neurodegenerative disorder, manifested in about 1% of the aged population. People who have Parkinson's Disease gradually lose control of their movements; specific symptoms include, "tremor, slowness of movement, stiffness, difficulty in walking, and loss of balance." (1) Evidence strongly suggests that Parkinson's Disease is the result of severe cell loss in the substantia nigra. This brain structure is principally involved in the production of dopamine. (2) Dopamine, among other functions, is the neurotransmitter involved in initiation of movement. Hence, the link between dopaminergic cell loss and cessation of voluntary movement, as manifested in Parkinson's Disease, seems established. (3) However, the applicability of this link seems to not end with Parkinson's Disease. If a severe deficit in dopamine induces cessation of movement and baseline levels of dopamine make voluntary, normal movement possible, can an excess of dopamine, or inc reased effectiveness of dopamine, lead to involuntary manifestation of movement? Potentially, a marked excess, or increase in effectiveness, of dopamine will lead to a loss of control of movement, just as a shortage of dopamine will. However, in the former case, movement should be involuntarily manifested. If such manifestations indeed were observed, it would be interesting to see if, in fact, dopamine excess, or dopamine at all, plays a role. Indeed, involuntary movements, commonly referred to as tics, are the primary symptoms of a disease called Tourette's Syndrome. The syndrome, named after the person who first described it, Gilles de la Tourette, "is a complex neurobehavioral disorder characteri... ...8,9,10) It is noteworthy, that these drugs, when used at excessive dosages, may lead to side effects such as muscular rigidity, tremor, slow movement, and other symptoms, which are very similar to the symptoms accompanying Parkinson's. Also, these side effects can be counteracted by administration of l-Dopa, a drug commonly given to overcome severe 'freezing' in Parkinson's patients. This evidence completes the picture that was anticipated when beginning to look at Parkinson's and a possible functional opposite. Normal movement does not suffice to serve as an opposite of Parkinson's; the severe tics accompanying Tourette's Syndrome, however, do. The evidence form drug studies and binding research serves to elucidate the connection. Internet Sources: http://www.jneurosci.org/cgi/content/abstract/17/9/3168 http://www.mentalhealth.com/drug/p30-o01.html#Head_1 Parkinson's Disease and Tourette's Syndrome Essay -- Biology Essays Re Parkinson's Disease and Tourette's Syndrome Parkinson's Disease is a literally crippling neurodegenerative disorder, manifested in about 1% of the aged population. People who have Parkinson's Disease gradually lose control of their movements; specific symptoms include, "tremor, slowness of movement, stiffness, difficulty in walking, and loss of balance." (1) Evidence strongly suggests that Parkinson's Disease is the result of severe cell loss in the substantia nigra. This brain structure is principally involved in the production of dopamine. (2) Dopamine, among other functions, is the neurotransmitter involved in initiation of movement. Hence, the link between dopaminergic cell loss and cessation of voluntary movement, as manifested in Parkinson's Disease, seems established. (3) However, the applicability of this link seems to not end with Parkinson's Disease. If a severe deficit in dopamine induces cessation of movement and baseline levels of dopamine make voluntary, normal movement possible, can an excess of dopamine, or inc reased effectiveness of dopamine, lead to involuntary manifestation of movement? Potentially, a marked excess, or increase in effectiveness, of dopamine will lead to a loss of control of movement, just as a shortage of dopamine will. However, in the former case, movement should be involuntarily manifested. If such manifestations indeed were observed, it would be interesting to see if, in fact, dopamine excess, or dopamine at all, plays a role. Indeed, involuntary movements, commonly referred to as tics, are the primary symptoms of a disease called Tourette's Syndrome. The syndrome, named after the person who first described it, Gilles de la Tourette, "is a complex neurobehavioral disorder characteri... ...8,9,10) It is noteworthy, that these drugs, when used at excessive dosages, may lead to side effects such as muscular rigidity, tremor, slow movement, and other symptoms, which are very similar to the symptoms accompanying Parkinson's. Also, these side effects can be counteracted by administration of l-Dopa, a drug commonly given to overcome severe 'freezing' in Parkinson's patients. This evidence completes the picture that was anticipated when beginning to look at Parkinson's and a possible functional opposite. Normal movement does not suffice to serve as an opposite of Parkinson's; the severe tics accompanying Tourette's Syndrome, however, do. The evidence form drug studies and binding research serves to elucidate the connection. Internet Sources: http://www.jneurosci.org/cgi/content/abstract/17/9/3168 http://www.mentalhealth.com/drug/p30-o01.html#Head_1