Marijuana's therapeutic potential and long-term neurological effects

¶ … Dangers of Marijuana

Marijuana is a popular recreational drug. Users smoke marijuana for the euphoric feeling that it produces. Traditionally, marijuana has been considered to be a drug of no therapeutic use. It is considered a dangerous addictive drug that is often a "gateway" to the use of more dangerous addictive drugs. However, researchers are now investigating this drug for more therapeutic usage. The use of marijuana for medical purposes is controversial, not only in the public domain, but in the medical society itself. The following will investigate marijuana and its potential use as a curative for several high-profile conditions as well as the dangers associated with it.

The effects of marijuana intoxication include the sensation that time passes more slowly, and an altered awareness of the body and environment around the person (Murray, 1985). There are also a number of emotional changes that occur as well. Intoxication with marijuana produces difficulty with motor coordination, impaired learning, difficulty paying attention and memory loss (Murray 1985). Compared to other psychotropic drugs such as cocaine and MDMA (Methamphetamine), marijuana is considered to be relatively harmless (Lundquist 2005). However, some long-term effects, such as neurotoxicity are a concern regarding the long-term medical use of the plant.

Marijuana is derived from a plant in the cannabis family. The intoxicating effect is produced by smoking or eating the aerial parts of the plant. The active component of marijuana is 9-tetrahydrocannabinol (THC). It also contains other active components such as cannabidiol, cannabinol, and 9-tetrahydrocannabinic acid. These are the key components that contribute to the psychotropic effects of the plant (Farthing 1992).

Pharmacology

Marijuana produces its characteristic effects when THC attaches to cannabinoid receptors and begins a chemical chain reaction. There are two primary cannabinoid receptors; CB1 and CB2. Only activation of the CB1 receptor can produce the euphoric state. A high concentration of CB! receptors can be found in the cerebellum and the basal ganglia area. This is the part of the brain that regulates our perception of time and awareness of our physical body. A concentration of CB1 receptors is also found in the cerebral cortex, which regulates our perception and ability of reason. Physiological evidence correlates with the effects observed in trials on memory loss and concentration (Gazzaniga et al. 1998).

The cannabinoid receptors and associated neurons make up a system called the endocannabinoid system. The endocannabinoid system regulates neurotransmitters by inhibiting the release of various inhibiting compounds in areas such as the hippocampus, cortex, and striatum (Rueda et al. 2002). Endocannabinoids inhibit neurogenesis (making new neurons), an important factor in histological and immunological responses of the body, such as cancer and rheumatoid arthritis (Rueda et al., 2002).Cannabinoids acting on the CB1 receptor play a role in protecting the brain from swelling and other forms of injury (Kim et al. 2006).

Medical Uses of Marijuana

The medical uses of marijuana have been recorded since 1850 when it was prescribed as a cure for gout, tetanus, depression, and cramps (Farthing 1992). The medical uses for marijuana today include reduction of intraocular pressure due to glaucoma, to relieve the nausea associated with chemotherapy, and as an appetite stimulant for AIDS patients (Farthing 1992). As one can see, there are many more potential uses of marijuana than the recreational use that is typically highlighted in popular media. However, this is not to say the marijuana is good for everyone, it simply means that the side effects and long-term effects warrant more serious consideration than they have in the past, particularly through the use of clinical trials for efficacy and safety.

Marijuana holds promise in the treatment of diseases such as Parkinson's and Huntington's disease, neuropathic pain, multiple sclerosis and spinal cord injury, to cancer, atherosclerosis, myocardial infarction, stroke, hypertension, glaucoma, obesity/metabolic syndrome, and osteoporosis (Pacher, Batkai, and Kunos 2006). The CB1 receptor may be useful in the alleviation of psychological disorders associated with fear (Kamprath et al. 2006).

CB2 is located in a common virus integration site and is over produced in certain types of leukemia (Jorda 2004). CB1 and CB2 receptor levels are significantly higher in prostate cancer cells. It has been suggested that CB1 and CB2 receptor antagonists may help treat prostate cancer (Sarfaraz et al. 2005). Lymphoma also expresses high levels of CB1 and CB2 receptor cells. Cannabinoids, such as THC, have antagonistic effects of CB1 cells in lymphoma (Gustafsson et al. 2006). Non-psychoactive cannabinoids, such as cannabidiol (CBD) have also shown antagonistic effects on glioma cells (Massi et al. 2003).

However, cannabinoids and vanilloids were found to reduce cell death in certain types of cancer cells (Maccarrone et al., 2000). This would actually promote the growth of cancer. Cannabinoids reduce nausea, vomiting, and pain in those undergoing treatment for cancer. However, a disturbing study found that it actually stimulates cancer cell growth and the progression of the disease (Hart et al. 2004). A new cannabinoid quinine, cannabidiol hydroxyquinone (HU-331), was found to have the ability to restrict the blood supply of cancer in such as way inhibits its growth (Kogan et al. 2006). The CB2 receptor holds many more potential uses in medicine and does not produce the psychotropic effects sought by habitual users.

Long-term habitual marijuana use is dangerous and causes long-term damage in the brain. The general health of the person has an effect on their ability to recover after the damage has occurred. The length and amount of use effect the ability to recover from these effects. As far as medical use is concerned, the potential dangers of use will have to be weighed against the potential dangers of the disease. For instance, long-term memory loss may not be desirable, but it may be better than glioma. There is still a long way to go in the use of marijuana for medical use. However, for the lay person, the dangers of long-term marijuana use are clear.