TY - JOUR AB - Cutaneous antidromic vasodilatation and plasma extravasation, two phenomena that occur in neurogenic inflammation, are partially blocked by substance P (SP) receptor antagonists and are known to be mediated in part by mast cell-released substances, such as histamine, serotonin, and nitric oxide. In an attempt to provide a morphological substrate for the above phenomena, we applied light and electron microscopic immunocytochemistry to investigate the pattern of SP innervation of blood vessels and its relationship to mast cells in the skin of the rat lower lip. Furthermore, we examined the distribution of SP (neurokinin-1) receptors and their relationship to SP-immunoreactive (IR) fibers. Our results confirmed that SP-IR fibers are found in cutaneous nerves and that terminal branches are observed around blood vessels and penetrating the epidermis. SP-IR fibers also innervated hair follicles and sebaceous glands. At the ultrastructural level, SP-IR varicosities were observed adjacent to arterioles, capillaries, venules, and mast cells. The varicosities possessed both dense core vesicles and agranular synaptic vesicles. We quantified the distance between SP-IR varicosities and blood vessel endothelial cells. SP-IR terminals were located within 0.23-5.99 μm from the endothelial cell layer in 82.7% of arterioles, in 90.2% of capillaries, and in 86.9% of venules. Although there was a trend for SP-IR fibers to be located closer to the endothelium of venules, this difference was not significant. Neurokinin-1 receptor (NK-1r) immunoreactivity was most abundant in the upper dermis and was associated with the wall of blood vessels. NK-1r were located in equal amounts on the walls of arterioles, capillaries, and venules that were innervated by SP-IR fibers. The present results favor the concept of a participation of SP in cutaneous neurogenic vasodilatation and plasma extravasation both by an action on blood vessels after binding to the NK-1r and by causing the release of substances from mast cells after diffusion through the connective tissue. AU - Ruocco, Isabella AU - Cuello, Augusto AU - Shigemoto, Ryuichi AU - Ribeiro Da Silva, Alfredo ID - 2604 IS - 4 JF - Journal of Comparative Neurology SN - 0021-9967 TI - Light and electron microscopic study of the distribution of substance P-immunoreactive fibers and neurokinin-1 receptors in the skin of the rat lower lip VL - 432 ER - TY - JOUR AB - Glutamate receptors have been linked to the regulation of several developmental events in the CNS. By using cortical slices of early postnatal mice, we show that in layer I cells, glutamate produces intracellular calcium ([Ca2+]i) elevations mediated by ionotropic and metabotropic glutamate receptors (mGluRs). The contribution of mGluRs to these responses was demonstrated by application of tACPD, an agonist to groups I and II mGluRs, which evoked [Ca2+]i increases that could be reversibly blocked by MCPG, an antagonist to groups I and II mGluRs. In the absence of extracellular Ca2+, repetitive applications of tACPD or quisqualate, an agonist to group I mGluRs, elicited decreasing [Ca2+]i responses that were restored by refilling a thapsigargin-sensitive Ca2+ store. The use of specific group I mGluR agonists CHPG and DHPG indicated that the functional mGluR in layer I was of the mGluR1 subtype. Subtype specific antibodies confirmed the presence of mGlur1α, but not mGluR5, in Cajal-Retzius (Reelin-immunoreactive) neurons. AU - Martínez, Galán AU - López Bendito, Guillermina AU - Luján, Rafael AU - Shigemoto, Ryuichi AU - Fairén, Alfonso AU - Valdeolmillos, Miguel ID - 2606 IS - 6 JF - European Journal of Neuroscience SN - 0953-816X TI - Cajal-Retzius cells in early postnatal mouse cortex selectively express functional metabotropic glutamate receptors VL - 13 ER - TY - JOUR AB - For an absolutely continuous probability measure μ. on ℝd and a nonnegative integer k, let S̃k(μ, 0) denote the probability that the convex hull of k + d + 1 random points which are i.i.d. according to μ contains the origin 0. For d and k given, we determine a tight upper bound on S̃k(μ, 0), and we characterize the measures in ℝd which attain this bound. As we will see, this result can be considered a continuous analogue of the Upper Bound Theorem for the maximal number of faces of convex polytopes with a given number of vertices. For our proof we introduce so-called h-functions, continuous counterparts of h-vectors of simplicial convex polytopes. AU - Wagner, Uli AU - Welzl, Emo ID - 2419 IS - 2 JF - Discrete & Computational Geometry SN - 0179-5376 TI - A continuous analogue of the Upper Bound Theorem VL - 26 ER - TY - JOUR AB - This paper concerns the asymptotic ground state properties of heavy atoms in strong, homogeneous magnetic fields. In the limit when the nuclear charge Z tends to ∞ with the magnetic field B satisfying B ≫ Z4/3 all the electrons are confined to the lowest Landau band. We consider here an energy functional, whose variable is a sequence of one-dimensional density matrices corresponding to different angular momentum functions in the lowest Landau band. We study this functional in detail and derive various interesting properties, which are compared with the density matrix (DM) theory introduced by Lieb, Solovej and Yngvason. In contrast to the DM theory the variable perpendicular to the field is replaced by the discrete angular momentum quantum numbers. Hence we call the new functional a discrete density matrix (DDM) functional. We relate this DDM theory to the lowest Landau band quantum mechanics and show that it reproduces correctly the ground state energy apart from errors due to the indirect part of the Coulomb interaction energy. AU - Hainzl, Christian AU - Seiringer, Robert ID - 2348 IS - 1 JF - Communications in Mathematical Physics SN - 0010-3616 TI - A discrete density matrix theory for atoms in strong magnetic fields VL - 217 ER - TY - JOUR AB - We consider the ground state properties of an inhomogeneous two-dimensional Bose gas with a repulsive, short range pair interaction and an external confining potential. In the limit when the particle number N is large but ρ̅a 2 is small, where ρ̅ is the average particle density and a the scattering length, the ground state energy and density are rigorously shown to be given to leading order by a Gross–Pitaevskii (GP) energy functional with a coupling constant g~1/|1n(ρ̅a 2)|. In contrast to the 3D case the coupling constant depends on N through the mean density. The GP energy per particle depends only on Ng. In 2D this parameter is typically so large that the gradient term in the GP energy functional is negligible and the simpler description by a Thomas–Fermi type functional is adequate. AU - Lieb, Élliott AU - Seiringer, Robert AU - Yngvason, Jakob ID - 2347 IS - 1 JF - Communications in Mathematical Physics SN - 0010-3616 TI - A rigorous derivation of the Gross-Pitaevskii energy functional for a two-dimensional Bose gas VL - 224 ER -