Local Regulation

Resistance in the arterioles of the working muscles is regulated locally. As discussed previously, active hyperemia results in production of several factors that cause metabolic vasodilation. Exercising muscles generate COz, H+ and K+ ions, heat, and adenosine. The vasodilator effect of these locally produced substances overrides the vasoconstrictor effect of the sympathetic system in the muscle. As a result, local vascular resistance is decreased. The combination of increased driving pressure and decreased local vascular resistance causes an increase in blood flow to the working muscles. 

Si, K., Giustetto, M., Etkin, A. et al. A neuronal isoform of CPEB regulates local protein synthesis and stabilizes synapse-specific long-term facilitation in aplysia. Cell 115 893-904, 2003. 

Fig. 9.1. A dysfunctional or injured endothelium is at the basis for initiation of and progression to atherosclerosis. Several mechanisms, such as adhesion molecules or liberation of von Willebrand factor (vWf, upper panel), determine a series of phenomena, including platelet activation and aggregation. This participation of platelets involves the implication of molecules like glycoprotein Ilb/IIIa, fibrinogen, and von Willebrand factor. The endothelium also acts as a source of signals that regulate local functions, including VSMCs (lower panel). A list of the most relevant messengers produced by a functional and a dysfunctonal endothelium is presented in the lower panel...

Solid wastes differ from air and water pollutants since these wastes remain at the point of origin until a decision is made to collect and dispose of them. There are several means of disposal available including recycling, chemical conversion, incineration, pyrolysis, and landfill. Federal regulations, local conditions, and overall economics generally determine which method is the most acceptable. 

Trlazoles of the type (440) are useful for regulating local plant growth (8iMiP4iloo). Trialkyl(l,2,3-triazolyl)tin compounds (441) can be used as biocides (81GEP293695i). 

Rocks O, Peyker A, Kahms M, Verveer PJ, Koerner C, Lumbierres M, Kuhlmann J, Waldmann H, Wittinghofer A, Bastiaens PIH. An acylation cycle regulates localization and activity of palmitoylated Ras isoforms. Science 2005 307 1746-1752. 

Thepen, T., Hoeben, K., Breve, J. and Kraal, G. (1992a). Alveolar macrophages down-regulate local pulmonary immune responses against intratracheally administered T cell-dependent, but not T cell-independent antigens. Immunology 76, 60-64. 

Visconti, P.E., Moore, G.D., Bailey, J.L., Leclerc, P., Connors, S.A., Pan, D., Olds-Clarke, P., and Kopf, G.S. (1995b). Capacitation of mouse spermatozoa. 11. Protein tyrosine phosphorylation and capacitation are regulated by a cAMP-dependent pathway. Development I21 1139-1150. Visconti, P.E., Johnson, L., Oyaski, M., Pomes, M., Moss, S.B., Gerton, G.L., and Kopf. G.S. (1997). Regulation, localization, and anchoring of protein kinase A subunits during mouse sperm capacitation. Dev. Biol. 792 351-363. 

Many of these changes In membrane fatty acid composition probably act by modulating enzymic activity by regulating localized or bulk membrane fluidity however, since most studies have not measured rates or ranges of lipid or protein motion as a function of changes In fatty acid composition, or even differentiated between total cell and phospholipid composition, there Is little direct support for this hypothesis. An additional complication Is the possible presence of laterally segregated lipid domains which could have profound effects on protein assembly or enzyme activity with minimal changes In bulk membrane fluidity. 

Baljuls A, Beck M, Oenel A, Robubi A, Kroschewski R, Hekman M, Rudel T, Rapp UR. The tumor suppressor DiRas3 forms a complex with H-Ras and C-RAF proteins and regulates localization, dimerization, and kinase activity of C-RAF. J Biol Chem. 2012 287 23128 0. 

For the above reasons, even if the heat transfer function of the vascular system has been appreciated since the mid-nineteenth century, only in the past 2 decades, has there been a revolution in our understanding of how temperature is controlled at the local level, both in how local microvascular blood flow controls the local temperature field and how the local tissue temperature regulates local blood flow. 

Pericytes, contractile cells contained within the sheath of the capillary basement membrane, represent 17 % of the total interstitial cell population in the normal human lung (Pinkerton et al. 1988). They demonstrated intensive membrane contacts with endothelial cells and commonly bridged endothelial cell lining adjacent capillary lumina. The close apposition of pericytes with the abluminal surfaces of endothelial cells may serve a potential function of regulating local blood flow through the pulmonary capillary bed. 

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