Taurine nervous tissue

Fig. 24-25), another component of nervous tissue. Cysteic acid can arise in an alternative way from O-acetylserine and sulfite (reaction 1, Fig. 24-25), and taurine can also be formed by decarboxylation of cysteine sulfinic acid to hypotaurine and oxidation of the latter (reaction m). Cysteic acid can be converted to the sulfolipid of chloroplasts (p. 387 Eq. 20-12). 

TAURINE EFFECTS ON CALCIUM TRANSPORT IN NERVOUS TISSUE... 

Taurine is not an exclusive constituent of nervous tissue it is also present at very high levels in contractile and secretory tissues. Since, except for the synthesis of taurocholic acid, taurine does not participate in metabolic reactions, its occurrence in animal tissues at substantial amounts should be related with a specific function which remains still unknown. If we consider that most taurine in nervous system is not related with a function as a neurotransmitter, the possibility that a single role is played by taurine in nervous, contractile or secretory tissues may be raised. Evidently, a multiplicity of taurine roles may also be envisaged, but we rather favour the hypothesis of a single action, probably at a basic mechanism underlying contractile, secretory and nervous function. A common denominator in all these functions is a modification of calcium gradients related to the excitation state of the tissue and a subsequent redistribution of calcium in order to return towards the resting intracellular levels. Taurine... 

Glutamate is the main excitatory amino acid neurotransmitter in central and peripheral nervous systems. Its concentration in brain is higher than in other body tissues. In the brain, the concentration of glutamate is 3- to 4-fold greater than that of aspartate, taurine, or glutamine (McGeer et al., 1987). The most abundant amino acid... 

Taurine - A glyclne-like, sulphur containing amino acid, taurine (12) is found in reasonably high concentrations throughout the mammalian central nervous system and in heart.In brain, taurine is formed as a result of the decarboxylation of cysteine sulphinic acid (15) to hypotau-rlne (8 ), which in turn is oxidized to form taurine.Like other transmitter candidates, taurine is accumulated and released by brain tissue and the accumulation can be inhibited by ouabain. Clinically, significant alterations in taurine levels may be associated with retinitis pigmentosa, epilepsy, mongolism, and possibly heart disease. 

Recently, it was found that unconjugated bile acids (CA, CDCA, and DCA) are present at high (nmol/g tissue) levels in the rat brain cytoplasmic fraction, but their functions in the central nervous system are unclear. To clarify this point, a profile analysis of file rat serum bile acids (eight common bile acids and their glycine and taurine conjugates) has been demonstrated. ... 

Outside the central nervous system, taurine in high concentrations is present in the heart, in striated muscle, in the adrenal gland, and in platelets and lymfocytes, but all tissues contain some taurine. 

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