Concanavalin modulation

The first allosteric modulators discovered to act on AMPA/KA receptors were the plant lectins, including concanavalin A (ConA), that block receptor desensitization, probably through binding to Y-1 inked oligosaccharides (51,52). It was soon discovered that certain benzothiazides, such as diazoxide and cyclothiazide, also act on the same allosteric site controlling non-NMDA receptor desensitization (53-55). Interestingly, ConA and cyclothiazide show high selectivity for KA and AMPA receptors, respec-... 

Recent studies with BN 52021 have demonstrated that PAF can modulate various immune processes. BN 52021 can inhibit the suppressive effect of PAF on T-lymphocyte proliferation and cytokine production. When PAF is added to human peripheral blood lymphocyte cultures (containing 5-10% monocytes) stimulated with phytohaemaglutinin (PHA) or concanavalin A (Con A), a non-toxic concentration-dependent inhibition of lymphocyte proliferation is... 

From the observation that the partitioning behavior of each protein was not affected by the presence of the others (38, 49), Goklen and Hatton resolved a mixture of cytochrome-c, ribonuclease-A and lysozyme, three low molecular weight proteins comprised in the range 12.4 - 14.3 kDa. With the same reversed micellar phase, Woll et (49) showed that the selectivity of extraction between ribonuclease-A and concanavalin-A could be modulated by vaiying the surfactant concentration a 40% enhancement... 

Nakano Y, Pross SH, Friedman H (1992) Modulation of interleukin 2 activity by delta-9-tetrahydrocannabinol after stimulation with concanavalin A, phytohemagglutinin, or anti-CD3 antibody. Proc Soc Exp Biol Med 201 165-168... 

Compounds that positively modulate the AMPA receptor have been reviewed [146, 147]. The first reports of AMPA receptor modulators, appearing over 20 years ago, were plant lectins (e.g., concanavalin A) that inhibited rapid non-NMDA receptor desensitization [148]. Shortly after, the nootropic drug 12 (aniracetam) (Fig. 3), which was reported to effect learning and memory, was found to selectively... 

The originally reported antisecretory activity of copper complexes [22] has, at least in part, been explained as antihistaminic activity or as a modulation of the activity of histamine (Tables 6.17-6.21) [261, 263, 267, 269], This suggestion is consistent with observations that copper markedly increases (50-fold) specific cimetidine bonding to brain membrane receptors [278-280]. Cimetidine has also been shown to form stable copper complexes [298,299] and the computer-simulated interactions of it with copper in plasma have been investigated [300, 301]. It is also known that copper decreases compound 48/80 and concanavalin-A-induced releases of histamine from peritoneal mast cells [281]. Further explanation of these antisecretory effects have been attributed to modulated syntheses of prostaglandins E2 and F2 [271], which is consistent with other reports of copper complex modulation of prostaglandin syntheses [282-286]. 

Partin, K.M., Patneau, D.K., Winters, C.A., Mayer, M.L. anu Buonanno, A. (1993). Selective modulation of desensitization at AMPA versus kainate receptors by cyclothiazide and concanavalin A. Neuron 11 1069-1082. 

Fernandis, A.Z. Subrahmanyam, G. Concanavalin A modulates tyrosine phosphorylation and activation of a type II phosphatidylinositol 4-kinase in rat splenic lymphocytes. Mol. ImmimoL, 35, 935-941 (1998)... 

Spectroscopic effects observed in the near-u.v. of c.d. spectra of concanavalin A are associated with the binding of metals at sites SI and S2. ° Time-dependent changes, as measured by the intrinsic Cotton effects, for Ga and the binding of methyl a-D-mannopyranoside were modulated by a symmetrical broad transition. A tentative structural hypothesis, which designates L-tyrosine-112 as an intrinsic reporter, is advanced to account for the spectroscopic observations. 

Several processes in the immune response are affected by lithium in vivo and in vitro [51-55]. The proliferative responses of hamster lymphoid cells to concanavalin A or phytohemagglutinin were enhanced by lithium in a serum-free culture system. Parietal cell, thyroid, and antinuclear antibodies have been reported to be increased in lithium-treated patients [56]. Pituitary autoantibodies have been demonstrated in lithium-treated patients. Tissue-specific autoantibodies such as these may or may not be related to autoimmune disease lithium may, in any case, modulate preexisting autoimmune processes rather than induce them. 

Delafuente, J. C., and Panush, R. S., 1979, Modulation of certain immunologic responses by vitamin C. II. Enhancement of concanavalin A-stimulated lymphocyte responses, Int. J. Vitam. Nutr. Res., 50 44. 

The major glycoproteins of the thymocyte plasma membrane which react with concanavalin A do not readily associate with other membrane proteins. It is possible that these concanavalin A-binding glycoproteins directly or indirectly modulate thymocyte function via their control of plasma membrane transport and/or permeability. 

L. Binderup, E. Bramm and E. Arrigoni-MarteHi, D-penicillamine and macrophages. Modulation of lymphocyte transformation by concanavalin A (in press). 

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