All issues
Successor
Volume 30 (1980)
- Issue 6 Pages 815-
- Issue 5 Pages 671-
- Issue 4 Pages 491-
- Issue 3 Pages 313-
- Issue 2 Pages 143-
- Issue 1 Pages 1-
Volume 30, Issue 5
Displaying 1-14 of 14 articles from this issue
- |<
- <
- 1
- >
- >|
-
Noriko SATAKE, Yutaka MATSUMURA, Mamoru FUJIMOTO1980 Volume 30 Issue 5 Pages 671-687
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSWith regard to pH measurement of biological fluids in vivo with metal-metal oxide microelectrodes, the effect of temperature and partial pressure of oxygen on antimony (Sb) microelectrodes was examined, and pH of blood was estimated in the bullfrog.
The temperature coefficient (dE/dt) of electromotive force (EMF) of Sb-microelectrodes in the range of 7 to 37°C was -1.18±0.113 mV/°C (mean±SEM) in Ringer solution, whereas that of the pH glass electrode in the same solution was -0.43±0.035 mV/°C. When estimated in Tris buffer solution, it was -0.06±0.063 mV/°C for Sb-microelectrodes and 1.05±0.036 mV/°C for glass electrodes.
The change of slope constant (α in-mV/pH) in the Sb-microelectrode due to temperature change could be predicted empirically from:α=0.40 (t-25) +55.3, where t represents the measuring temperature in °C.
The resultant deviation of pH readings between Sb and glass electrodes, ΔpHsb-Glass, may be expressed by:
ΔpHsb-Glass=0.00183 (t-25) +0.016.
In the range of 45 to 760 mmHg of oxygen partial pressure at fixed pH, the EMF increased linearly with the increase of PO2, the slope (dE/dlog (PO2)) being 11.7±0.42 (SEM) mV (n=13, t=25°).
In consideration of the above effects, the blood pH of bullfrog was estimated to be 7.697±0.092 (SD) and 7.729±0.111 with glass and Sb-microelectrodes respectively, the difference between the two being relatively minor.View full abstractDownload PDF (1483K) -
Noriko SATAKE, Yutaka MATSUMURA, Mamoru FUJIMOTO1980 Volume 30 Issue 5 Pages 689-700
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSIn order to examine the effect of protein on the Sb-microelectrode used for the pH measurement of biological fluids, bovine serum albumin (BSA) and plasma protein were used for test samples. It was found that, BSA, probably by binding to components in the electrode system, produced a marked deviation of both the electromotive force and slope constant of the microelectrode, resulting in an alkaline shift of pH of 0.1-0.7. But the shift of the pH reading could be empirically predicted within an error of±0.03 from the cubic function of protein concentration.Use of Tris standard solution as the calibration buffer, together with corrections for the effects of temperature, ionic strength, PO2, etc. on the Sb-microelectrode, would reduce the alkaline shift to approximately less than 0.08 and 0.04 pH units in the pH measurement of blood plasma and whole blood, respectively.View full abstractDownload PDF (1109K) -
Yasuyuki SUGANO, Tetsuo NAGASAKA1980 Volume 30 Issue 5 Pages 701-708
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSThe effects of obstruction of the air passage through the nose on hypothalamic temperature (Thy) and heat balance were studied in 37 conscious rabbits using a direct calorimeter.The obstruction of the air passage through the nose was made by forcing the animal to breathe through a tracheal bypass cannula at a calorimeter wall temperature (Tw) of either 17, 22, 26, or 28°C.By bypass breathing, Thy and sensible heat loss (HL dry) were increased without a significant change in colonic temperature in a warm environment. At Tw 28°C, Thy in bypass breathing was 39.52±0.13°C while that in nose breathing was 39.30±0.11°C (p<0.05). HL dry in bypass breathing was 29.3±0.8 W·m-2 while that in nose breathing was 24.8±0.6 W·m-2 (p<0.01).However, evaporative heat loss (HLwet) was not changed by bypass breathing, although the respiratory rate was increased slightly.These results indicate that the obstruction of air passing through the nose increases hypothalamic temperature and elicites a thermolytic response only through the increase in sensible heat loss in the Tw 28°C environment.Heat production (M) was not suppressed by bypass breathing at Tw 28°C, at which the value of M was already minimum (42.0±3.0 W⋅ m-2).In the 17-26°C range of Tw, heat balance was roughly obtained in either nose or bypass breathing.At Tw 28°C, however, M was slightly higher than HL, and a positive shift of heat storage was assumed particularly in nose breathing.View full abstractDownload PDF (870K) -
Yutaka TAKATA1980 Volume 30 Issue 5 Pages 709-728
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSRegional differences in electrical and mechanical properties of guinea-pig mesenteric vessels were investigated using microelectrode and isometric tension recording methods.The amplitude of membrane potentials differed according to region and in the following order; branch of jejunal artery (BJA)>cranial mesenteric artery (CMA)>jejunal artery (JA)≤ jejunal vein (JV) portal vein (PV).There were also regional differences in the muscle membrane potential with various concentrations of [K] o or [Na] o, while no differences were observed with applications of various concentrations of [Ca] o or [Cl] o.ACh produced hyperpolarization of the muscle membrane in the CMA, JA and JV but not in the PV and BJA.Hyperpolarization in the JA mainly followed increase in the Kpermeability, and a reversal potential for ACh was distributed at about -70mV.In the JV, the ACh-induced hyperpolarization accompanied tension development.Phenylephrine depolarized the muscle membranes of the CMA, JA and PV but not of the BJA and JV.Low concentrations of phenylephrine produced contractions with no depolarization of the membrane in the JA and CMA.Isoprenaline-induced hyperpolarization was smaller in arteries than in veins, and this hyperpolarization was reduced in amplitude with repeated applications.The AChinduced relaxation and phenylephrine-induced contraction were larger in the JA than in the CMA.Regional differences of the muscle property in response to application of different agents were discussed in relation to the physiological roles.View full abstractDownload PDF (1789K) -
Mitsuhiko MATSUMOTO, Kazuhiko SASAKI, Kohsuke SOMEI, Makoto SATO1980 Volume 30 Issue 5 Pages 729-742
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSVarious types of acetylcholine (ACh) receptor in the pleural or abdominal ganglion cells of Aplysia were classified into three types depending on the ion species involved in the electrogenesis of their responses.The Na-dependent receptor was designated the DNa-type since the response was a depolarization (D) produced by an increase in permeability, mainly toward Na+, although other ions were partially involved.Similarly, the Cl- or K-dependent receptor was designated the HCl- or HK-type since the response was a hyperpolarization (H) produced by an exclusive increase in permeability toward Cl- or K+.AChinduced responses were evaluated by an increase in membrane conductance.
The DNa-type receptor could be readily activated by tetramethylammonium (TMA) and choline, but not by decamethonium (Deca).Instead, it was blocked competitively either by hexamethonium (Hexa) or by Deca.The HCl-type receptor could be readily activated by TMA, choline, and Deca.Hexa did not block this type of receptor.The HK-type receptor was neither activated nor blocked by TMA, choline, Hexa, and Deca.
The above findings suggested that there is a certain structural similarityin the ACh-binding site between DNa-type and HCl-type receptors, although the ion species involved in the electrogenesis of each responsewere totally different.The structure of the ACh-binding site at theHK-type receptor seemed considerably different from that of eitherDNa-type or HCl-type.View full abstractDownload PDF (1371K) -
Mitsuhiko MATSUMOTO, Kazuhiko SASAKI, Kohsuke SOMEI, Makoto SATO1980 Volume 30 Issue 5 Pages 743-750
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSMost of the classical studies on the mode of inhibition by various inhibitors specific to the postsynaptic receptors have been done by observing dose-response curves with a parameter of inhibitor concentration. The aim of this paper is to describe a new method we derived from conventional enzyme kinetics and to examine the applicability of this method to practical experiments for analyzing receptor-inhibitor interactions. The relative change in agonist-induced response in the presence of the inhibitor was plotted against inhibitor concentration in logarithmic scale. This curve may be called a dose-inhibition curve with a agonist concentration parameter.
Our theory makes the following predictions:
(1) If the curve shifts to the right with the increase in agonist concentration, the mode of inhibition should be competitive;
(2) If the curve shifts to the left with the increase in agonist concentration, the mode of inhibition should be uncompetitive;
(3) If the curve remains unchanged with the change in agonist concentration, the mode of inhibition should be noncompetitive.
In order to examine the applicability of this method, we chose the excitatory type of acetylcholine-induced responses of the ganglion cells in Aplysia, and analyzed the mode of inhibition by decamethonium (Deca) and tetraethylammonium (TEA). This type of analysis suggested that the mode of inhibition by Deca was competitive whereas that by TEA was noncompetitive.View full abstractDownload PDF (716K) -
Masayosi GOTO, Cham-ming SUN, Atsuko YATANI, Mami URATA, Takao FUJINO1980 Volume 30 Issue 5 Pages 751-765
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSAction of α-and β-agonists on the membrane potential, current and tension components on the bullfrog atrial muscle were studied by means of the single or double sucrose-gap technique. Isoproterenol (10-9-10-5M) as well as adrenaline (10-7-10-4M) produced a dose-dependent positive inotropic effect, while methoxamine (10-8-10-4M) and phenylephrine (10-8-10-3M) with propranolol (10-6M) elicited a negative inotropic effect. The positive inotropic effect was accompanied by slight hyperpolarization and marked increase of overshoot and plateau level of action potential, and the negative inotropic effect, by opposite changes. Under voltage clamp, isoproterenol and adrenaline produced enhancement of slow inward current (Is), delayed outward current (Ix) and Is-dependent phasic tension, while Is-independent tonic tension was inhibited. Contrarily, methoxamine and phenylephrine depressed these currents and elicited β-antagonistic inotropic actions, especially when isoproterenol was present. Specific feature of α-agonist action in the presence of isoproterenol was an inward shift of the semi-steady I-V relationship. It is thus suggested that, in the bullfrog atrium, α-agonists produce a strong β-receptor blocking action and an inward shift of the background current. A possible relationship between the latter effect and inhibition of the Na-K pump is also suggested.View full abstractDownload PDF (1595K) -
Shiro KASAI, Waka TERASAWA, Hiroaki KODAMA, Takashi TERASAWA1980 Volume 30 Issue 5 Pages 767-774
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSThe effect of spleen extract from irradiated rats on CFU-e and BFU-e colony formation of rat bone marrow cells was investigated by using modified plasma clot culture media.
In the presence of erythropoietin (Ep), CFU-e colony formation peaked at 48 hr of culture, and the Ep-induced increase of CFU-e colonies was dose-dependent.The addition of spleen extract enhanced the colony formation more than two-fold in the Ep-containing culture.BFU-e colony formation was also enhanced by the addition of spleen extract.These results indicate that spleen extract from irradiated rats contains factor (s) which stimulates the proliferation of erythroid progenitors.View full abstractDownload PDF (3411K) -
Takahiro KUBOTA, Minoru HONDA, Kunihiko KOTERA, Mamoru FUJIMOTO1980 Volume 30 Issue 5 Pages 775-790
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSEffects of extracellular diffusible ions, such as K+, Cl- and HCO3- (pH), on the peritubular membrane potential (EM) and intracellular activities of K+, (K) i, or Cl-, (Cl) i, were studied in the perfused proximal tubule of bullfrog kidneys with K+ or Cl--selective microelectrodes. In steady-state conditions, in which both the peritubular and luminal sides were perfused with control Ringer solutions, the K+ equilibrium potential (EK) always exceeded the EM by approximately 19 mV and correlated well with the EM (correlation coefficient r=0.78), whereas no correlation was recognized between the equilibrium potential of Cl- (ECl) and the EM.
In the quick peritubular perfusion experiments, in which the extracellular diffusible ions were changed, the (K) i and (Cl) i were maintained relatively stable.The following facts were observed:(1) At constant EK, decreasing the peritubular chloride (Cl) e produced a small degree of hyperpolarization of the EM instead of depolarization.(2) At constant ECl, increasing the (K) e depolarized the EM.(3) At constant Pco2, the EM was depolarized with low HCO3- (acid) perfusions, while it was hyperpolarized with high HCO3- (alkaline) perfusions.
These results are in agreement with the views that, 1) intracellular K+in the proximal tubule is maintained by an uphill uptake mechanism onthe peritubular cell membrane, (2) the ionic conductance of peritubular membrane is relatively high to K+, but low to Cl-, and (3) the pH gradient across the peritubular membrane can modulate the passive permeability to Na+ or K+.View full abstractDownload PDF (1670K) -
Masataka MURAKAMI, Hirohiko MORI, Takashi NAKAHARI, Yusuke IMAI1980 Volume 30 Issue 5 Pages 791-794
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSA simple method for measuring rates of blood flow through a glandular tissue and the salivary secretion was devised by using an electronic balance.The method proved to have a sufficiently high time resolution and accuracy.View full abstractDownload PDF (351K) -
Tsuyoshi MIZONISHI1980 Volume 30 Issue 5 Pages 795-798
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSLowering of the intra-antral pressure caused enhanced movements of the corporal pouch in the dog stomach.Stimulation of the central end of vagal fibers supplying the antrum also augmented movements of both the antral pouch and corporal pouch.The findings suggest the existence of a gastro-gastric excitatory reflex which plays a role in gastric emptying.View full abstractDownload PDF (412K) -
Tetsuo NAGASAKA, Kozo HIRATA, Hiroyuki SHIBATA, Yasuyuki SUGANO1980 Volume 30 Issue 5 Pages 799-803
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSWhen conscious rats were physically restrained, their body temperature, heart rate and heat production increased within minutes. The rate of increase in heat production was less than that in heart rate, particularly in warm environments.Reduction of oxygen pulse, consequently either stroke volume or(A-V)O2difference, was suggested. Stroke volume, cardiac output and its fractional distribution to most of the calorigenic organs measured by the reference sample method using85Sr-labelled microspheres decreased significantly by restraint. However, fractional distribution of cardiac output increased greatly to the skeletal muscles.The restraint-hypermetabolism may be attributed to the increased metabolism of the skeletal muscles supported with an increased availability of oxygen.With a slight increase in mean aortic pressure, total peripheral resistance increased greatly as observed during Valsalva-like maneuver.The decrease in cardiac output and stroke volume during restraint may be caused by obstruction to the systemic venous return.View full abstractDownload PDF (551K) -
Yoshiaki ISOBE, Kokichi OHARA, Mitsuo KOSAKA, Kyuzo AOKI1980 Volume 30 Issue 5 Pages 805-810
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSRectal temperature, catecholamine contents in the hypothalamus, and blood pressure were measured in spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats (WKY).SHR had a significantly higher rectal temperature than WKY.Noradrenaline contents were lower in SHR than WKY.Noradrenaline was inversely correlated with the blood pressure e and body temperature in SHR.In subgroups of SHR, differences in values of the parameters mentioned above were also observed.View full abstractDownload PDF (531K) -
Goro KATSUURA, Ryoji HIROTA, Shinji ITOH1980 Volume 30 Issue 5 Pages 811-814
Published: 1980
Released on J-STAGE: June 07, 2011
JOURNAL FREE ACCESSIn order to elucidate the central action mechanism of choiecystokinin (CCK), effects of this peptide on norepinephrine, dopamine and serotonin contents in the brain were observed in saline control, α-methyl-p-tyrosine-, L-DOPA- and pargyline-pretreated rats.Intraperitoneal injection of CCK in a dose of 40U/kg did not produce any significant changes in the monoamine contents.However, since a tendency to increase in norepinephrine turnover rate after CCK injection was noticed, the possibility that brain monoamines are involved in the central action of CCK could not be excluded.View full abstractDownload PDF (430K)
- |<
- <
- 1
- >
- >|