Pineal system

Van Gelder Marty Zatz has shown that the chick pineal system has at least two components, one that is vitamin A-depletable and one that is not. This suggests multiple photopigments even in the pineal photo-sensation. 

The following data ( fable 1) for niolcctilcs, including hydrocarbon s, strained ring system s. molecn les with heieroatom s, radicals, and ions conies from a review by Stewart. For most organic molecules,, YM 1 reports heals of formation accurate to within a few kilocalories per rn ol. bor soni e molecules (particularly inorgari ic compoun ds wdth several halogens, such as perch loryl fluoride, even the best sem i-em pineal method fails completely. 

However, despite its enormous importance to human physiology, no pharmacological compounds targeting the components of the circadian clock system have been identified to date. There are, nevertheless, two therapeutic approaches that are currently used for treatment of circadian-related disorders - full-spectrum and bright light therapy and melatonin therapy. Melatonin is a hormone that is produced by the pineal gland in... 

Amphioxus ( 500xl06 years) As for (1) with an eye spot. Some coordination of sight with the body. No evidence of olfactory or hearing senses. Little or no telencephalox or cerebral cortex. Has forebrain, pineal and hypothalamus like systems... 

A3 adenosine receptors are few in the central nervous system. In the rat, abundant A3 transcript is found exclusively in testes. However, the transcript for similar sheep and human receptors is modestly expressed throughout the brain and heavily expressed in pineal gland, lung and spleen. 

Serotonin is present in a variety of sites in the brain. Its role as a neurotransmitter and its relation to the actions of drugs acting in the central nervous system are discussed in Chapters 21 and 30. Serotonin is also a precursor of melatonin in the pineal gland (Figure 16-2 ... 

There are many nerve fibers in the pineal gland. Some of these fibers release noradrenalin, a chemical messenger produced by the nervous system. Noradrenalin stimulates certain cells in the pineal gland, called pinealocytes, to produce and release melatonin. 

In patients with DSPS, a delay in the timing of physiological and behavioral systems that demonstrate circadian rhythmicity is reported, compared to normally entrained individuals. This delay is evident in a variety of functions, including secretion of the pineal hormone melatonin (e.g., Ref. 162), thermoregulation, and sleep-wake activity. Individuals with DSPS typically experience difficulty initiat-... 

One further treatment that has been studied extensively to achieve resynchronization of the circadian system is the administration of melatonin. Endogenous melatonin is secreted from the pineal gland, primarily across the nocturnal or dark period. It has been proposed to play a role in the control of the circadian system (reviewed in Ref. 174) and potentially in the initiation of sleep (175,176). Studies that have administered exogenous melatonin, primarily during the daytime, have reported both chronobiotic (177) and soporific effects (178). Melatonin administration has been successful in studies examining the reentrainment of the circadian system after transmeridian flight or shiftwork (179). Similarly, the effectiveness of melatonin in reentraining the circadian system of those with DSPS to a normal day has been studied. 

Hormones are secreted by specialized glands (adrenal, hypothalamus, ovary, pancreas, parathyroid, pineal, pituitary, testes, thyroid) or other tissues (e.g., heart, gut, and kidney), and regulate the cellular activities of distant tissues. Plasma levels of hormones are tightly regulated through homeostatic feedback systems. The peptide and protein hormones typically have short half-lives (minutes), which allow rapid changes in plasma levels and rapid enhancement or attenuation of their biological effects. 

Koyama FC, Ribeiro RY, Garcia JL et al (2012) Ubiquitin proteasome system and the atypical kinase PfPK7 are involved in melatonin signaling in Plasmodium falciparum. J Pineal Res Jan 30 [Epub ahead of print] doi 10.111 l/j,1600-079X.2012.00981.x... 

At least three types of proton channel systems are recognized in animal cells. These include the Na+/H+ exchanger, the H+-ATPase, and the HCOj/Cl- exchanger. It is clear that a major part of proton release by some cells in response to transplasma membrane electron transport is by activation of the Na+/H+ exchanger. This is clear from the characteristics of the proton movement elicited and the magnitude of H+ release in relation to electron flow when electron transport is activated. Activation of electron transport can be elicited by addition of di-ferric transferrin to activate the transmembrane NADH oxidase activity or by electron flow to external ferricyanide from internal NADH. Addition of di-ferric transferrin to certain cells, especially pineal cells, elicits a remarkable proton release and internal alkaliniza-tion. The stoichiometry of H+ release to iron reduced is more than 100 to 1 (Sun et... 

Not only does the body make its own narcotics, it also makes representatives t)f most of the other categories of drugs discussed in this hook. It certainly makes its own uppers in the form of adrenaline and noradrenaline. It makes its own downers in the form of serotonin and GABA (gamma-amino-butyric acid), chemicals that slow down transmission in the central nervous system. Sex hormones can be powerful antidepressants, working better than anything so far concocted in a laboratory. Probably the body also makes its own psychedelics — most likely DMT (dimcthyl-tryptamine ) or a close relative of it — since the pineal gland, deep in the brain, secretes hormones with a very similar molecular structure. 

Pineal gland A tiny, light-sensitive organ in the center of the brain, also called the pineal eye or "third eye." In reptiles it controls changes in skin color. In humans it is a master gland of the endocrine system, probably regulating many biorhythms. 

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