Proceedings of the National Academy of Sciences of the United States of America, Vol. 68, No. 12. (December 1971), pp. 3107-3110.
Saturday, February 28, 2009
Melatonin metabolism
There is a diurnal rhythm in the activity of serotonin N-acetyltransferase in the rat pineal gland. In the normal rat, the nocturnal enzyme activities are 15-to 30-fold greater than are daytime activities. This rhythm is abolished by decentralization or removal of the superior cervical ganglia, procedures that interrupt the only source of central neural input to the pineal gland. This effect of superior cervical sympathectomy on the N-acetyltransferase rhythm cannot be attributed to changes occurring in the denervated pineal parenchymal cells. When chronically denervated glands are placed in organ culture with norepinephrine, the neurotransmitter normally located in sympathetic terminals in the gland, N-acetyltransferase activity increases 10- to 20-fold. These data indicate that superior cervical sympathectomy abolishes the N-acetyltransferase rhythm by elimination of the input of central signals to the gland. These signals appear to regulate the N-acetyltransferase rhythm in the normal rat by regulation of the release of norepinephrine from the sympathetic terminals within the pineal gland.
Melatonin, serotonin
Cervical sympathetic nerves may affect blood adrenocorticotropic hormone (ACTH), cortisol (CS), melatonin or serotonin levels. We examined whether stellate ganglion block (SGB), which inhibits this nerve conduction, affects these substances.
During surgery, melatonin circadian rhythm and serotonin levels did not change, but melatonin increased only at night and serotonin decreased after surgery. These findings suggested that some stress stimuli are conducted via cervical sympathetic nerves to the hypothalamus, which is reduced by SGB, and to the pineal gland at night, which causes increased melatonin and decreased serotonin levels.
During surgery, melatonin circadian rhythm and serotonin levels did not change, but melatonin increased only at night and serotonin decreased after surgery. These findings suggested that some stress stimuli are conducted via cervical sympathetic nerves to the hypothalamus, which is reduced by SGB, and to the pineal gland at night, which causes increased melatonin and decreased serotonin levels.
Authors: Iwama, Hiroshi; Son, Syoraku; Watanabe, Kazuhiro
Source: The Pain Clinic, Volume 13, Number 3, 2001 , pp. 233-244(12)
Publisher: Maney Publishing
Melatonin production abolished after sympathectomy
The amount of 6-sulphatoxymelatonin, the chief metabolite of melatonin, in the urine was measured in nine patients, who were subjected to
bilateral sympathectomy at the second thoracic ganglionic level for treatment of hyperhidrosis of the palms. All patients showed before surgery had a normal 6-sulphatoxymelatonin excretion with a peak in the excretion during the night time. After the sympathectomy, the high night time excretion
was clearly abolished in five patients but remained high in four patients. This indicates that the segmental locations of the preganglionic sympathetic perikarya in the spinal cord, stimulating the melatonin secretion in the pineal gland in humans, vary between individuals.
© 2006 Elsevier Ireland Ltd. All rights reserved.
Molecular and Cellular Endocrinology 252 (2006) 40–45
Melatonin
Melatonin is an important immunomodulator and is the principal means by which tissues are synchronized
to the daily cycle of light exposure and physical actity. Cortisol, on the other hand, is critical for
maintaining energy homeostasis and modulating immune function. Melatonin and cortisol tend to run opposite
to each other. That is, cortisol approaches its low point at bedtime, whereas melatonin reaches its peak a few
hours aft corti bottoms out (see Figure 1 below). Deviations from the normal patterns for these hormones can
have significant implications for overall health and future risk of cancer. In fact, research shows that low
melatonin and high cortisol are independently associated with some of the same health conditions.
Consequently, the balance between these two hormones is important to overall good healt. The melatonin-
cortisol index (MCI)s an innovative way of examining the balance between these two vital hormones. The MCI may be used to assess cancer risk and immune function, and may also aid in the assessment of depression, heart disease, osteoporosis and weight management issues.
Melatonin | Rocky Mountain Analytical Lab
http://www.rmalab.com/index.php?id=61
bilateral sympathectomy at the second thoracic ganglionic level for treatment of hyperhidrosis of the palms. All patients showed before surgery had a normal 6-sulphatoxymelatonin excretion with a peak in the excretion during the night time. After the sympathectomy, the high night time excretion
was clearly abolished in five patients but remained high in four patients. This indicates that the segmental locations of the preganglionic sympathetic perikarya in the spinal cord, stimulating the melatonin secretion in the pineal gland in humans, vary between individuals.
© 2006 Elsevier Ireland Ltd. All rights reserved.
Molecular and Cellular Endocrinology 252 (2006) 40–45
Melatonin
Melatonin is an important immunomodulator and is the principal means by which tissues are synchronized
to the daily cycle of light exposure and physical actity. Cortisol, on the other hand, is critical for
maintaining energy homeostasis and modulating immune function. Melatonin and cortisol tend to run opposite
to each other. That is, cortisol approaches its low point at bedtime, whereas melatonin reaches its peak a few
hours aft corti bottoms out (see Figure 1 below). Deviations from the normal patterns for these hormones can
have significant implications for overall health and future risk of cancer. In fact, research shows that low
melatonin and high cortisol are independently associated with some of the same health conditions.
Consequently, the balance between these two hormones is important to overall good healt. The melatonin-
cortisol index (MCI)s an innovative way of examining the balance between these two vital hormones. The MCI may be used to assess cancer risk and immune function, and may also aid in the assessment of depression, heart disease, osteoporosis and weight management issues.
Melatonin | Rocky Mountain Analytical Lab
http://www.rmalab.com/index.php?id=61
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