Mammalian brain tissue

Moncrieff J. (1989). Determination of pharmacological levels of harmane, harmine, and harmaline in mammalian brain tissue, cerebrospinal fluid, and plasma by high-performance liquid chromatography with fluorimetric detection. J Chromatogr. 496(2) 269-78. 

Very little is known about the biosynthesis of the three most recently proposed endocannabinoids, 2-AGE, virodhamine and NADA. Regarding 2-AGE (noladin ether), this compound was previously identified in pig brain (Hanus et al. 2001) and in some rat tissues and brain areas (Fezza et al. 2002) by using mass-spectrometric (MS) methods coupled to chromatographic separations. However, a recent study cast some doubt on the actual existence of 2-AGE in mammalian brain tissue (Oka et al. 2003). At the time of this study it was already known that (1) the only acyl ethers to have been detected in animals before the discovery of 2-AGE were 2-acyl ethers (e.g. alkenyl ethers such as platelet activating factor and plasmalogens) (2) there was no evidence for the existence of any enzyme catalysing the formation... 

The presence of o-serine in mammalian brain tissue was first reported in 1989 [33, 34]. It has recently been established that o-serine is employed in the mammalian forebrain as a co-agonist for the N-methyl-o-asparate (NMDA) excitatory amino acid receptor [35, 36]. A PLP-dependent serine racemase has been cloned and purified from mammalian brain, and found to be a homodimer, which has a number of nonessential cofactors that enhance its activity, including Ca +, Mg + and ATP [37-40]. The mouse brain enzyme has also been shown to catalyze elimination from L-serine, to form pyruvate, with an activity comparable to that for racemiza-tion [41]. Interestingly, the first instance of this class of racemase was discovered by Esaki and coworkers in the silkworm, Bombyx mori [42]. o-serine concentration in the blood of B. mori larvae is thought to play a role in metamorphosis. 

Glutamine synthetase catalyzes the ATP-dependent biosynthesis of glutamine according to equation (1). This enzyme plays a central role in nitrogen metabolism. In mammalian brain tissue, glutamine synthetase converts the neurotransmitter glutamate into glutamine. 

NADPH diaphorase is an enzyme that catalyzes NADPH-dependent reduction of a tetrazoUum salt, such as nitro blue tetrazohum (NBT), into an insoluble colored formazan. In theory, any NADPH-requinng enzyme could exhibit NADPH diaphorase activity. However, when NADPH diaphorase histochemistry was applied to aldehyde-fixed mammalian brain tissue, only a specific population of neurons stained (6). These NADPH-diaphorase-positive neurons did not correspond to any of the known classical neurotransmitter systems and they remained a mystery until the discovery of NO-producing neurons in the brain. 

Dor6, C. F., and Richards, C. D., 1974, An improved chamber for maintaining mammalian brain tissue slices for electrical recording, J. Physiol. 239 83-85P. 

Prod, in vivo by hydrol. of phosphatidylinositol 4,5-diphosphate. Present in mammalian brain tissue. Important cellular second messenger. Controls Ca release from intracellular stores. Cryst. (MeOH aq.) (as tri-Na salt), [a] -11.1 (c, 0.9 in H2O) (tri-Na salt). Mp >270° (as tri-Na salt). Chiral, D-form. 

Lalwani G, Sai Pavan G, Mahapatra O, Gopalakrishnan C, Arunachalam KD. Study of effects of tetradotoxin (TTX) on mammalian brain tissue using iron nanoparticle (TTX) conjugate. Int J Mater Sci (IJoMS) 2009 4 529-40. 

Fig. 6. /. The chemical structure of anandamide(N-arachidonoylethanolaminel an endogenous cannabinoid substance identified in mammalian brain tissue.

Originally, it was assumed that while the CBi receptor is found primarily in the brain and neuronal tissue, while the CB2 receptor is found exclusively outside the central nervous system, primarily in immune tissue. However, Van Sickle etal. reported the expression of CB2 receptor mRNA and protein localization on brainstem neurons. Recently, it was demonstrated that CB2 receptor and their gene transcripts are also distributed in the mammalian brain. The levels of CB2 receptors in brain are... 

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