54 Pineal 02

Pineal Gland

The pineal gland is a small organ attached by a stalk to the posterior wall of the third ventricle of the brain in vertebrate animals. Lying above the cerebellum, it is richly supplied with blood vessels and nerve fibers. In certain fishes, frogs, and lizards, the gland is associated with a well-developed light-sensitive organ, or so-called "third eye," and in all species the pineal is affected by light. The gland produces a hormone, called melatonin, from the neurotransmitter serotonin. This hormone is associated in varying and not yet well-understood ways with a number of biorhythms (see biological clock), including such long-term ones as the onset of puberty, and appears to be particularly important in animals that display seasonal behavior.

Bibliography: Arendt, Josephine, "The Pineal: A Gland that Measures Time?" New Scientist, July 25, 1985; Evered, D., and Clark, S., eds., Photoperiodism, Melatonin and the Pineal (1986); Gupta, Derek, and Reiter, R. J., The Pineal Gland during Development (1986).

Vide também:
http://www.triplov.com/crespo/pineal.html
http://www.cultura_racional2003.kit.net/a_glandula_pineal.htm
http://www.comciencia.br/reportagens/envelhecimento/texto/env10.htm
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