A blog maintained by Tevita Kete, PGR Officer
Secretariat of the Pacific Community (SPC), Suva, Fiji Islands
This weblog documents the activities of Pacific Agricultural Genetic Resources Network (PAPGREN), along with other information on plant genetic resources (PGR) in the Pacific.
The myriad varieties found within cultivated plants are fundamental to the present and future productivity of agriculture. PAPGREN, which is coordinated by the Land Resources Division of the Secretariat of the Pacific Community (SPC), helps Pacific countries and territories to conserve their crop genetic diversity sustainably, with technical assistance from the Bioversity International (BI) and support from NZAID and ACIAR.
SPC also hosts the Centre of Pacific Crops and Trees (CEPaCT). The CEPaCT maintains regional in vitro collections of crops important to the Pacific and carries out research on tissue culture technology. The CEPaCT Adviser is Dr Mary Taylor (MaryT@spc.int), the CEPaCT Curator is Ms Valerie Tuia (ValerieT@spc.int).
PAPGREN coordination and support
Mr William Wigmore
Mr Adelino S. Lorens
Dr Lois Englberger
Mr Apisai Ucuboi
Dr Maurice Wong
Mr Tianeti Beenna Ioane
Mr Frederick Muller
Mr Herman Francisco
Ms Rosa Kambuou
Ms Laisene Samuelu
Mr Jimi Saelea
Mr Tony Jansen
Mr Finao Pole
Mr Frazer Bule Lehi
Interested in GIS?
Thursday, August 07, 2003
Posted 2:53 PM by Luigi
Kava on the brain
This from a recent New Scientist (19 July 2003) Q&A.
I recently drank some of the interesting root-based drink kava on the Pacific island of Vanuatu. I'm happy to report that it had some odd effects. What exactly did it do to my brain?
Robert Steers , Galston, New South Wales, Australia
1. Because your correspondent drank the kava in Vanuatu, it may have been made using either fresh or dried roots, while in other countries where kava is drunk namely, Fiji, Tonga and Samoa it is almost exclusively prepared from dried roots. Vanuatu kava, especially that from fresh material, is much more potent and its effects tend to be greater. The active chemical ingredients in kava, called kavalactones, produce a number of effects in both the brain and the rest of the body. Initially the tongue becomes numb, as does the inner lining of the mouth. Some of the other effects may depend on the familiarity of the user with the drink. A novice user may find the drink bitter or sour and that food loses its taste and flavour. Nausea may follow, along with headache and intestinal discomfort, effects not experienced by the habitual drinker.
In contrast to alcohol, kava used in moderate amounts produces a calming effect, reduces fatigue, allays anxiety and stress, and induces a generally pleasant, cheerful and sociable attitude. It is partly for these reasons that it has been consumed in South Pacific communities for hundreds of years as a social drink. One hears expressions like, "you cannot hate with kava in you" and "unlike liquor, kava does not provoke aggressive, boisterous or violent behaviour". Nor does it cause the hangovers, physical addiction, memory loss or diminished reasoning associated with alcohol.
Kavalactones have been shown to produce a number of biological effects in the brain that could account for the above observations. They include the compounds' ability to produce a local anaesthetic-like effect hence the numbing of the tongue and to act on drug receptors in a similar way to some anxiety and stress medications such as benzodiazepine. As a result, kava was introduced in the western world to treat anxiety, stress, restlessness and sleep disorders.
However, less positive effects have been reported with the use of excessive amounts of kava, and in a few cases where it has been combined with medical drugs.
There have been some reports of kava causing liver damage in people who live in western nations where it has been used in the form of pills and other such preparations. Consequently, some countries have suspended the sale of kava or issued health advisories. As this medical condition has not been reported in traditional kava drinkers, it is unclear whether it is directly associated with kava itself, or with the manufacturing process or some other factors. In any case, kava is still widely drunk by people from the South Pacific, including myself I am originally from Fiji.
Yadhu Singh , Brookings, South Dakota, US
2. Exactly how kava acts on the brain is unknown. Benzodiazepine anti-anxiety drugs work by stimulating the brain's gamma-aminobutyric acid (GABA) receptor proteins, which regulate signal transmission between nerve cells, but kava is not thought to work on GABA and is also thought to act in a different way to the opioid drugs. It may work on the brain's limbic system, located in the medial temporal lobe of the brain, which is involved in controlling emotions. There has been speculation that it may antagonise the neurotransmitter chemical dopamine.
Jamie Horder , Oxford, UK
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