運動特性の違いによる伸張反射機能の特異的適応

修士論文要

Control of rat glomerular microcirculation by juxtaglomerular adenosine A1 receptors

Control of rat glomerular microcirculation by juxtaglomerular adenosine A1 receptors. The role of adenosine A1 receptors in the glomerular microcirculation and tubuloglomerular feedback (TGF) was studied in anesthetized Sprague-Dawley rats. TGF activity was assessed as the reduction in proximal tubular stop-flow pressure (SFP) on establishing orthograde perfusion of the loop of Henle with artificial tubular fluid at 40 nl/min. Administration of a selective A1 receptor antagonist, KW-3902 (0.5 μg/kg/min i.v.), increased fractional excretion of Na (FENa) 4.3-fold without changing blood pressure, glomerular filtration rate, renal plasma flow, or filtration fraction. SFP in the absence of distal flow (SFP0) increased, and TGF-mediated SFP reduction was suppressed dose dependently [by 23 ± 2% from an SFP0 of 34 ± 1mm Hg, by 15 ± 4% from 36 ± 2mm Hg, and by 2 ± 1% from 39 ± 1mm Hg during vehicle, low- and high-dose infusions (0.5 and 5.0 μg/kg/min), respectively]. Intratubular or peritubular capillary administration of 10-4m KW-3902 completely suppressed TGF without affecting SFP0. TGF suppression and elevation of SFP0 during systemic A1 blockade indicated vasodilation, both in the afferent arteriole and more proximal preglomerular vessels. Inhibition of tubular Na reabsorption combined with TGF suppression allowed the marked natriuresis. TGF suppression through systemic, luminal, and peritubular application of the drug suggest that juxtaglomerular apparatus A1 receptors are important in the control of glomerular microcirculation

The successful strategy for mutual cooperation in the experimental multi-game contact

Playing multiple games simultaneously is popular, but we hardly know how people act in this situation to reach mutual cooperation in the long run. To answer the question, we conduct a series of experiments on multi-game contact. The results indicate that the number of information sets in the stage game and the payoff structure are important. We find that for making mutual cooperation subjects employ two types of TFT strategies, which simplify the complicated contact. In these strategies, they avoid separating behavior such as cooparating in one game but deviating in the other. This makes it easy for the opponents to understand thier cooperative intention

Topology conserving gauge action and the overlap-Dirac operator

We apply the topology conserving gauge action proposed by Luescher to the four-dimensional lattice QCD simulation in the quenched approximation. With this gauge action the topological charge is stabilized along the hybrid Monte Carlo updates compared to the standard Wilson gauge action. The quark potential and renormalized coupling constant are in good agreement with the results obtained with the Wilson gauge action. We also investigate the low-lying eigenvalue distribution of the hermitian Wilson-Dirac operator, which is relevant for the construction of the overlap-Dirac operator.Comment: 27pages, 11figures, accepted versio

Glucose or Sucrose Intakes and Plasma Levels of Essential and Nonessential Amino Acids

It is not known whether the administration of glucose or sucrose influences plasma levels of amino acids. We want to know whether plasma levels of amino acids and if the administration of glucose or sucrose are different in young and old men and are influenced by the administration of glucose or sucrose. We found that the levels of most amino acids in plasma are lower in old men than young men. When sucrose was administered to old men, levels of total amino acids decreased significantly in old men. In both old and young men plasma levels of total nonessential amino acids significantly decreased at 120 min. after the administration of glucose but not sucrose. On the other hand, total essential and branched amino acids levels decreased significantly after the administration of both glucose and sucrose in young and old men. From these results, responses to the administration of glucose were different from the response to sucrose between young and old men. Also glucose was more effective in decreasing plasma levels of various amino acids. These results seem to suggest that glucose was more effective in stimulating insulin release and young men were more responsive to sugar than old men in stimulating insulin release