Inhibitory regulators

Toro, M.J., E. Montoya, and L. Bimbaumer. 1987. Inhibitory regulation of adenylyl cyclases. Evidence inconsistent with beta gamma-complexes of Gi proteins mediating hormonal effects by interfering with activation of Gs. Mol. Endocrinol. 1 669-676. 

Inhibitory regulation of voltage-gated Ca2+ channels direct or indirect involvement of a G protein ... 

Ultrastructural characterization of the D2 receptors have revealed that they are often present within the GABA-containing cells within the striatum, cerebral cortex, hippocampus, globus pallidus and thalamic reticular nucleus (Mrzljak et al., 1996). Thus, dopaminergic transmission via the D2 receptors predominantly provides inhibitory local intrinsic control in the cerebral cortex and inhibitory regulation of the projection pathways. 

GABA (y-aminobutyric acid) is derived from glutamate by decarboxylation. It occurs predominantly in inhibitory synapses in the central nervous system, as does glycine. Tetanus toxin acts on glycinergic neurons in the spinal cord, which exert inhibitory regulation on the a-motoneurons. ... 

Kume, H., Graziano, M.P. and Kotlikoff, M.I. (1992). Stimulatory and inhibitory regulation of calcium-activated... 

An alternative mechanism for regulation of p42/p44 MAPK could be the release of the inhibitory regulation of c-Raf that results from the phosphorylation of Raf by PKA. CBi receptor/Gi-mediated inhibition of cyclic AMP production and reduction of PKA activity would promote a net dephosphorylation of c-Raf, thereby permitting the Raf kinase to serve as an activator of MEK in the p42/p44 MAPK activation module. Evidence for this pathway has been described for WIN55212-2-stimulated NlE-115 neuroblastoma cells (Davis et al. 2003) and hippocampal slice preparations (Derkinderen et al. 2003). 

The effect of noradrenaline on NGF release was correlated with a reduction in mRNA " levels within smooth muscle fibres and fibroblasts from the dissociated iris. Although the results of this experiment support the idea of an inhibitory regulation of NGF synthesis by sympathetic neurotransmitters, they involved the use of high concen-... 

Endocrine and metabolic effects Endocrine and metabolic effects include hyperprolactinemia, weight gain, gynecomastia, the amenorrhea-galactorrhea syndrome, and infertility. These effects are predictable manifestations of dopamine receptor blockade in the pituitary dopamine is the normal inhibitory regulator of prolactin secretion. 

A tryptophan-free diet results in a fall in brain serotonin levels after 4 hours. Lacking the inhibitory regulation of serotonin, neuronal activity is insufficientiy modulated, resulting in the person becoming angry, depressed and impulsive, losing control of emotions. 

Rich, K.A., Codina, J., Floyd, G., Sekura, R., Hildebrandt, J.D. and Iyengar, R. (1984). Glucagon-induced heterologous desensitization of the MDCK cell adenylyl cyclase Increases in the apparent levels of the inhibitory regulator. (Nj). ]. Biol Chem., 259, 7893-7901... 

Fig. 2. A scheme of the hypothalamic-anterior pituitary-target organ axis systems and pituitary adenoma pathogenesis (Mehned [8]). (+) Stimulatory regulation (-) inhibitory regulation. Reproduced from Zhan and Desiderio [14], with permission from Wiley-VCH, copyright 2005, and modified from Mehned [8], with permission from Copyright Clearance Center Inc. (Re Journal of Clinical Investigation), copyright 2003.

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