| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1
* Department of Pharmacology and
Center for Alcohol Studies, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599, USA
1Correspondence: Department of Pharmacology, CB #7365 Mary Ellen Jones Bldg., University of North Carolina, Chapel Hill, NC 27599-7365, USA. E-mail: thurman{at}med.unc.edu
 |
ABSTRACT |
|---|
 TOP ABSTRACT INTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
production
as a result of endotoxin (lipopolysaccharide, LPS) were attenuated by
feeding animals a diet enriched with glycine. This phenomenon was shown
to be a result of, at least in part, activation of a chloride channel
in Kupffer cells by glycine, which hyperpolarizes the cell membrane and
blunts increases in intracellular calcium concentrations
([Ca2+]i) similar to its action in the
neuron. It is well known that hepatotoxicity due to LPS has a
neutrophil-mediated component and that activation of neutrophils is
dependent on increases in [Ca2+]i. Therefore,
the purpose of this study was to determine if glycine affected
agonist-induced increases in [Ca2+]i in rat
neutrophils. The effect of glycine on increases in
[Ca2+]i elicited either by the
bacterial-derived peptide formyl-methionine-leucine–phenylalanine
(FMLP) or LPS was studied in individual neutrophils using Fura-2 and
fluorescence microscopy. Both FMLP and LPS caused dose-dependent
increases in [Ca2+]i, which were maximal at 1
µM FMLP and 100 µg/ml LPS, respectively. LPS increased
intracellular calcium in the presence and absence of extracellular
calcium. Glycine blunted increases in [Ca2+]i
in a dose-dependent manner with an IC50 of ~0.3 mM,
values only slightly higher than plasma levels. Glycine was unable to
prevent agonist-induced increases in [Ca2+]i
in chloride-free buffer. Moreover, strychnine (1 µM), an antagonist
of the glycine-gated chloride channel in the central nervous system,
reversed the effects of glycine (1 mM) on FMLP- or LPS-stimulated
increases in [Ca2+]i. To provide hard
evidence for a glycine-gated chloride channel in the neutrophil, the
effect of glycine on radioactive chloride uptake was determined.
Glycine caused a dose-dependent increase in chloride uptake into
neutrophils with an ED50 of ~0.4 mM, an effect also
prevented by 1 µM strychnine. Glycine also significantly reduced the
production of superoxide anion from FMLP-stimulated neutrophils. Taken
together, these data provide clear evidence that neutrophils contain a
glycine-gated chloride channel that can attenuate increases in
[Ca2+]i and diminish oxidant production by
this important leukocyte.—Wheeler, M., Stachlewitz, R. F.,
Yamashina, S., Ikejima, K., Morrow, A. L., and Thurman, R. G.
Glycine-gated chloride channels in neutrophils attenuate calcium influx
and superoxide production.
Key Words: glycine • strychnine • intracellular calcium • lipopolysaccharide • formyl-methionine-leucine-phenylalanine
|
INTRODUCTION |
|---|
|
TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
2
3
4)
. Because
depleting neutrophils or blocking their function before chemical or
hypoxic challenge protects tissues, it has been concluded that
neutrophils play a key role in pathophysiology (5
6
7
8)
.
Neutrophils participate in injury by adhering and invading tissue and
releasing superoxide, arachidonic acid metabolites, and proteases by
processes that are largely calcium dependent (9
10
11
12)
.
Recently, it was shown that glycine inhibited LPS-mediated
increases in [Ca2+]i in
Kupffer cells, the resident hepatic macrophage, by a mechanism
dependent on extracellular chloride (13)
. This effect was
reversed by strychnine, which is a well-characterized antagonist of the
glycine-gated chloride channel in the nervous system (14)
.
Activation of the neuronal glycine-gated chloride channel causes an
influx of chloride and hyperpolarizes the nerve cell membrane, making
opening of voltage-gated calcium channels on the cell surface more
difficult (15
, 16)
, thereby diminishing responses to a
variety of agonists that depolarize the cell membrane. In an analogous
fashion, glycine hyperpolarizes Kupffer cell membranes making calcium
channels on the plasma membrane more difficult to open
(17)
, which inhibits the production of cytokines
(13)
. Glycine also causes an influx of radiolabeled
chloride into the Kupffer cell (18)
. Moreover, molecular
evidence (i.e., mRNA and protein) for the ß-subunit of the
glycine-gated chloride channel similar to the spinal cord glycine-gated
chloride channel has been demonstrated in these macrophages
(19)
. Taken together, these studies led to the conclusion
that Kupffer cells contain glycine-gated chloride channels like the
neuron. Because the Kupffer cell is a specialized leukocyte derived
from the same pluripotent stem cell as neutrophils, the purpose of this
study was to determine if neutrophils, which are very important in many
inflammatory disease processes, contain a glycine-gated chloride
channel. Preliminary accounts of this study have appeared elsewhere
(20)
.
|
MATERIALS AND METHODS |
|---|
|
TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
Measurement of intracellular calcium
([Ca++]i) in adherent neutrophils
Cells (5x105 cells/plate) were
plated on glass coverslips and allowed to adhere for 20 min before
replacing the media with fresh RPMI 1640 containing 10% FCS and
antibiotics. Adherent neutrophils were incubated in modified Hank’s
balanced salt solution (m-HBSS, 110 mM NaCl, 5 mM KCl, 0.3 mM
Na2HPO4, 0.4 mM
KH2PO4, 5.6 mM glucose, 0.8
mM
MgSO4.7H2O,
1.26 mM CaCl2, 4 mM NaHCO3,
15 mM HEPES, pH 7.4) containing 5 mM Fura-2 acetooxymethyl ester for 60
min at room temperature. Coverslips were rinsed with m-HBSS and fresh
buffer was added. Intracellular calcium was assessed by monitoring
changes in fluorescence intensity of Fura-2 at excitation wavelengths
of 340 and 380 nm with emission at 540 nm in individual cells. Values
were corrected by subtracting system dark noise and autofluorescence by
adding Mn++.
[Ca2+]i was determined by
the method of Grynkiewicz et al. (21)
from the following
equation:
 |
. Peak increases in calcium concentration were
consistently achieved within 30 s after agonist addition.
Measurement of 36chloride uptake by neutrophils
Assays for uptake of 36Cl used an
adaptation of a method for neurons described by Schwartz et al.
(22)
modified by Morrow and Paul (23)
. In
brief, neutrophils (2x106 cells/ml) were plated
on glass coverslips and allowed to adhere for 1 h at 37°C. Media
was replaced with buffer (20 mM HEPES, 118 mM NaCl, 4.7 mM
MgSO4, 2.5 mM CaCl2, and 10
mM glucose) and allowed to equilibrate for 10 min at room temperature.
Coverslips were gently blotted dry and incubated in a petri dish with 2
ml of buffer containing 2 µCi/ml 36Cl in the
presence of glycine (0–2 mM) and/or strychnine (1 µM or 1 mM) for
5 s. Chloride influx was linear between 2–10 s; thus, a 5 s
incubation time was chosen for all experiments. Strychnine was
dissolved in DMSO, and the final concentrations of DMSO (0.002%) used
in these studies had no effect on 36Cl movement.
Chloride flux was terminated by washing the coverslip with ice-cold
buffer for 3 s followed by a second wash for 7 s
(23)
. Coverslips were placed in scintillation vials and
protein was solubilized by adding 1.6 ml of NaOH (0.2 M) for 2 h.
An aliquot (0.16 ml) was taken for determination of protein by the
method of Lowry (24)
. Ecolume (10 ml) was added and
radioactivity was determined by scintillation spectroscopy. Flux
measured in glycine-free buffer was subtracted from all values to
account for basal chloride movement across the cell membrane as well as
trapped radioactive chloride.
Measurement of superoxide release
Superoxide production was measured from the superoxide dismutase
(SOD)-inhibitable reduction of ferricytochrome c as
described previously (25)
. Incubation volume was 1.0 ml,
and the concentration of neutrophils was 2.0 x
106 cells/ml. Initially, cells were incubated
with glycine (1 mM) for 5 min at 24°C. Cytochalasin B (4 µM, final
concentration) was added to each tube and incubation continued at
37°C for 5 min to disrupt actin filaments.
Formyl-methionine-leucine–phenylalanine (FMLP) (1 µM) was added and
the incubation continued at 37°C for 30 min. The amount of reduced
ferricytochrome c was determined spectrophotometrically at
550 nm. The difference in absorption between the samples incubated in
the presence and absence of SOD (85 U/ml) was used to determine the
amount of superoxide produced, using an extinction coefficient for
reduced ferricytochrome c of
18500·cm-1·M-1
(26)
.
|
RESULTS |
|---|
|
TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
show transient increases in
[Ca2+]i after treatment
with FMLP (1 µM, Fig. 1A
) or LPS (100 µg/ml +5% rat
serum, Fig. 1B
). The effect of LPS was dependent on rat
serum because there is an absolute requirement for a species-specific
LPS binding protein for binding to CD-14 to occur (27)
.
The addition of rat serum alone had no effect on
[Ca2+]i in neutrophils
(data not shown). After exposure to either agonist, basal values near
30 nM [Ca2+]i increased
rapidly and reached peak values within 30 s. FMLP increased
[Ca2+]i to maximal values
of ~275 nM followed by a decline that reached a plateau at ~175 nM
within 1 min (Fig. 1A
). On the other hand, LPS (Fig. 1B
) caused a transient increase in
[Ca2+]I, which peaked at
250 nM and returned to basal values within 1 min. Moreover, incubation
with 1 mM glycine (see below) for 3 min had no effect on basal calcium
levels but totally prevented agonist-induced increases in
[Ca2+]i in neutrophils
(Fig. 1)
.
|
Concentration-response curves for agonists on increases in
[Ca2+]i
The effect of various concentrations of FMLP (Fig. 2
A) and LPS (Fig. 2B
) on
[Ca2+]i in single
adherent neutrophils were determined in experiments typified by Fig. 1
.
The effect of FMLP was maximal at 1 µM with an
ED50 of 0.44 µM. LPS increased
[Ca2+]i maximally at 100
µg/ml and had an ED50 of 45 µg/ml.
|
The effect of glycine on agonist-induced increases in
[Ca2+]i
Neutrophils were incubated in m-HBSS containing glycine (0–2 mM)
for 3 min before and during addition of agonist (Fig. 3
). Glycine blunted the increase in
[Ca2+]i in neutrophils
stimulated with either FMLP (1 µM, Fig. 3A
) or LPS (100
µg/ml, Fig. 3B
) and was not toxic to cells at any
concentration tested as determined by trypan blue exclusion. This
prevention of agonist-induced increases in
[Ca2+]i was linear
between 0 an 1 mM glycine treatment. From linear regression analysis,
the IC50 values for blunting increases in
[Ca2+]i after addition
the FMLP or LPS were both ~0.3 mM glycine.
|
It appeared that glycine prevented the agonist-induced increases in
[Ca2+]i almost
completely, suggesting that glycine blunted the release of calcium from
intracellular stores as well as calcium influx from extracellular space
Therefore, the effect of glycine on the calcium increase from
intracellular stores was evaluated in the absence of extracellular
calcium. Removal of the extracellular calcium and addition of EGTA had
little effect on the peak
[Ca2+]i after LPS
stimulation compared with cells stimulated in the presence of calcium
(Fig. 4
). However, the agonist-induced increase in
[Ca2+]i was prevented
completely by the addition of 1 mM glycine in both the presence or
absence of calcium.
|
The role of extracellular chloride in glycine-mediated inhibition
of agonist-induced increases in [Ca2+]i
It is known that glycine activates a glycine-gated chloride
channel in neurons and Kupffer cells, leading to chloride influx that
attenuates increases in
[Ca2+]i (13
, 15
, 16)
. It was hypothesized that glycine prevents FMLP- and
LPS-mediated increases in
[Ca2+]i in the neutrophil
by a similar mechanism. To test this hypothesis, chloride in the buffer
was substituted with gluconate. Indeed, in chloride-free buffer,
glycine (1 mM) was unable to block agonist-induced increases in
[Ca2+]i when cells were
stimulated either with FMLP or LPS (Fig. 5
).
|
Strychnine, at micromolar concentrations, is an inhibitor of the
glycine-gated chloride channel in the neuron and Kupffer cell
(13
, 14)
. Strychnine (1 µM) was added to cells before
stimulation with FMLP or LPS to test the hypothesis that it would also
reverse the effect of glycine in neutrophils (Fig. 6
). As shown above, both FMLP and LPS caused an increase in
[Ca2+]i that was totally
prevented by glycine. Indeed, the addition of 1 µM strychnine
reversed the effect of glycine and restored agonist-induced increases
in [Ca2+]i to near normal
levels.
|
In other cells, such as isolated kidney tubules and Kupffer cells,
strychnine inhibits the effect of glycine at low concentrations
(micromolar range) but has agonist actions like glycine in the
millimolar range (13
, 28)
. Indeed, high concentrations of
strychnine (1 mM) prevented agonist-induced increases in
[Ca2+]i like glycine with
both FMLP (80±25 nM) or LPS (61±16 nM) (Fig. 6)
.
Radiolabeled chloride is used routinely in cells to provide hard
evidence for movement of ions from the extracellular to the
intracellular space (22
, 23)
. Accordingly, adherent
neutrophils were incubated with 36Cl and
increasing concentrations of glycine (Fig. 7
A). Glycine caused a dose-dependent increase in
36Cl influx. The ED50 value
for glycine-stimulated chloride influx was 0.23 mM, which is
essentially the same value as the IC50 for
inhibition of agonist-induced increases in
[Ca2+]i by glycine.
Furthermore, the addition of 1 µM strychnine prevented chloride
influx due
to glycine almost completely, and high concentrations of strychnine (1 mM)
activated chloride influx essentially like glycine (Fig. 7B
)
.
|
Effect of glycine on superoxide production by neutrophils
It is known that production of superoxide by neutrophils is, in
part, calcium dependent (29)
. To determine if glycine
could inhibit calcium-dependent functions of neutrophils, the effect of
glycine on superoxide production was
studied. FMLP stimulated neutrophils to produce nearly 7.6 ± 0.4 nmol
superoxide/106 cells/30 min. Glycine (1 mM)
blunted superoxide production in isolated neutrophils significantly to
4.8 ± 0.5 nmol superoxide/106 cells/30 min
(n=4–6 per group, P<0.05, Student’s
t test).
|
DISCUSSION |
|---|
|
TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
and 2)
. FMLP caused a rapid
increase in [Ca2+]i
within seconds followed by a gradual decrease, which reached a plateau
and never returned to basal values, confirming work by others
(30)
. The initial increase in calcium most likely arises
from intracellular stores, whereas the sustained increase is the result
of influx of calcium from the extracellular space (31)
.
Although LPS also caused an increase in
[Ca2+]i, the mechanism of
LPS signaling and calcium mobilization in neutrophils is not clearly
understood. This is the first study showing that LPS can increase
calcium in neutrophils; however, relatively high concentrations of LPS
(100 µg/ml) are needed. LPS concentrations commonly used in in
vitro studies (32)
are higher than physiological
circulating LPS concentrations. Thus, the physiological significance of
the activation of neutrophils by LPS is not clear but may be important
in disease states such as septic shock where LPS levels are elevated
(33)
.
Neutrophils contain a glycine-gated chloride channel
The primary goal of this study was to determine if neutrophils
contain a glycine-gated chloride channel analogous to the channel in
the neuron and Kupffer cell (4
, 34)
. It was hypothesized
that glycine would prevent increases in
[Ca2+]i by
hyperpolarizing the cell
membrane, thereby preventing activation of voltage-dependent calcium channels.
Indeed, glycine blunted FMLP- and LPS-stimulated increases in
[Ca2+]i with an
IC50 ~0.3 mM (Fig. 3)
. This value is similar to
the IC50 values for prevention of LPS toxicity
and inhibition of activation of Kupffer cells by glycine and only about
twice as high as normal circulating concentrations. These blood levels
are easily achieved with a diet enriched with glycine (1)
.
In addition, it is concluded that glycine not only affects influx of
calcium from the extracellular space but also prevents release from
intracellular stores, because glycine totally prevented increases in
[Ca2+]i due to LPS and
FMLP both in the presence and absence of extracellular calcium (Fig. 4)
. The mechanism for this effect of glycine remains unclear. It has
been suggested that the IP3-gated chloride
channel on the endoplasmic reticulum may be inactivated when the
potential difference across the membrane is increased
(35)
. Thus, it is possible that influx of chloride across
the cell membrane also increases the potential difference across the
endoplasmic reticulum making the IP3-receptor
more difficult to open (see Fig. 8
).
|
Strychnine is a well known antagonist of glycine-gated chloride
channels (13
, 14)
. Here, 1 µM strychnine reversed the
effect of glycine, restoring the increase in
[Ca2+]i to near control
values (Fig. 6)
. These data provide pharmacological evidence for the
presence of glycine-gated chloride channels in neutrophils. High
concentrations of strychnine (1 mM) have been shown to be protective
against hypoxic injury in the perfused liver and isolated renal
proximal tubules as well as blunt increases in
[Ca2+]i in Kupffer cells,
which is apparently paradoxical to its effects on the glycine-gated
chloride channel. (13
, 28
, 36)
. In this study, a high
concentration of strychnine also prevented increases in
[Ca2+]i due to LPS and
FMLP and caused influx of chloride, essentially like glycine. Based on
these data, it is concluded that strychnine at high concentrations is
also an agonist for the glycine-gated chloride channel in the
neutrophil.
If the effect of glycine is a result of activation of a glycine-gated
chloride channel in the neutrophil, it would be dependent on the
presence of extracellular chloride. Indeed, substitution of chloride
with an impermeable anion gluconate prevented the inhibitory effect of
glycine on agonist-induced increases in
[Ca2+]i almost completely
(Fig. 5)
. Moreover, glycine increased radiolabeled chloride movement
into the neutrophil in a dose-dependent manner (Fig. 7)
with an
ED50 value almost identical to the
IC50 value for prevention of LPS- and
FMLP-induced increases in
[Ca2+]i. Strychnine (1
µM) prevented the influx of chloride, as expected, providing more
evidence that glycine blunts increases in
[Ca2+]i by activating a
glycine-gated chloride channel. Thus, it is concluded that glycine
activates a chloride channel in the neutrophil.
Based on the data presented above, it is hypothesized that glycine
inhibits processes in the neutrophil that are dependent on increases in
[Ca2+]i, such as
activation of NADPH oxidase and the production of superoxide radicals.
Indeed, glycine blunted superoxide production by neutrophils stimulated
with FMLP. The fact that glycine did not completely prevent superoxide
release from the neutrophil is not surprising, because there are
calcium-independent pathways (e.g., activation of tyrosine kinases)
that also mediate superoxide release from the neutrophil. However,
increases in intracellular calcium are required for optimal superoxide
generation from FMLP-stimulated neutrophils (9
10
11
12
, 29)
.
Proposed mechanism of action of glycine
Based on the data presented here, the following mechanism of
action of glycine in neutrophils is proposed (Fig. 8)
. When cells are
stimulated with either LPS or FMLP, signal transduction pathways are
activated that change the potential differences across the cell
membrane. In the presence of glycine, a glycine-gated chloride channel
is activated causing an influx of chloride, leading to
hyperpolarization of the neutrophil membrane. The increase in membrane
potential caused by agonists is blunted by glycine, which decreases the
opening time of voltage-dependent calcium channels on the cell membrane
and inhibits the influx of calcium. In addition, influx of chloride
could also inactivate the IP3-gated calcium
channel and blunt release of calcium from intracellular stores.
Decreased calcium influx blunts the activation of calcium-dependent
pathways in the cell inhibiting the function of the phagocyte.
Clinical applications of glycine
Glycine has several benefits that make its clinical application
appealing. First, glycine can be administered in the diet without side
effects (37)
. Second, data from this and previous studies
with Kupffer cells and alveolar macrophages (13
, 38)
show
that glycine is antiinflammatory and could be useful in many disease
states which are dependent on the activation of neutrophils and
macrophages (4)
. Indeed, it has been shown previously that
glycine prevents lethality due to LPS and in a model of
ischemia-reperfusion injury to the liver in vivo followed by
administration of LPS (two-hit model) (1)
. This model
mimics the increase in sensitivity of trauma patients to LPS. Moreover,
glycine was shown to be protective in the classical galactosamine
toxicity model, presumably by inactivation of Kupffer cells
(3)
. Currently, glycine has only been shown to be
effective prophylacticly; however, it could be potentially useful in a
wide variety of inflammatory processes where neutrophil infiltration
contributes to toxicity.
|
ACKNOWLEDGMENTS |
|---|
|
FOOTNOTES |
|---|
|
REFERENCES |
|---|
|
TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTSDISCUSSIONREFERENCES |
|---|
from alveolar macrophages is blunted by glycine. Am. J. Physiol. 277,L952-L959This article has been cited by other articles:
|
|
 |
|
  K. Lubick, M. Radke, and M. Jutila Securinine, a GABAA receptor antagonist, enhances macrophage clearance of phase II C. burnetii: comparison with TLR agonists J. Leukoc. Biol., November 1, 2007; 82(5): 1062 - 1069. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Busetto, E. Trevisan, E. Decleva, P. Dri, and R. Menegazzi Chloride Movements in Human Neutrophils during Phagocytosis: Characterization and Relationship to Granule Release J. Immunol., September 15, 2007; 179(6): 4110 - 4124. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 X. Zhou, W. Yang, and J. Li Ca2+- and Protein Kinase C-dependent Signaling Pathway for Nuclear Factor-{kappa}B Activation, Inducible Nitric-oxide Synthase Expression, and Tumor Necrosis Factor-{alpha} Production in Lipopolysaccharide-stimulated Rat Peritoneal Macrophages J. Biol. Chem., October 20, 2006; 281(42): 31337 - 31347. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. G. Moreland, A. P. Davis, G. Bailey, W. M. Nauseef, and Fred. S. Lamb Anion Channels, Including ClC-3, Are Required for Normal Neutrophil Oxidative Function, Phagocytosis, and Transendothelial Migration J. Biol. Chem., May 5, 2006; 281(18): 12277 - 12288. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. W. Lynch Molecular Structure and Function of the Glycine Receptor Chloride Channel Physiol Rev, October 1, 2004; 84(4): 1051 - 1095. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. E. Decoursey Voltage-Gated Proton Channels and Other Proton Transfer Pathways Physiol Rev, April 1, 2003; 83(2): 475 - 579. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 W. Qu, K. Ikejima, Z. Zhong, M. P. Waalkes, and R. G. Thurman Glycine blocks the increase in intracellular free Ca2+ due to vasoactive mediators in hepatic parenchymal cells Am J Physiol Gastrointest Liver Physiol, December 1, 2002; 283(6): G1249 - G1256. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Froh, R. G. Thurman, and M. D. Wheeler Molecular evidence for a glycine-gated chloride channel in macrophages and leukocytes Am J Physiol Gastrointest Liver Physiol, October 1, 2002; 283(4): G856 - G863. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Bray, J.-H. Son, P. Kumar, J. D. Harris, and S. Meizel A Role for the Human Sperm Glycine Receptor/Cl- Channel in the Acrosome Reaction Initiated by Recombinant ZP3 Biol Reprod, January 1, 2002; 66(1): 91 - 97. [Abstract] [Full Text]
|
|
|
|
 |
|
 Z. Zhong, X. Li, S. Yamashina, M. von Frankenberg, N. Enomoto, K. Ikejima, M. Kolinsky, J. A. Raleigh, and R. G. Thurman Cyclosporin A Causes a Hypermetabolic State and Hypoxia in the Liver: Prevention by Dietary Glycine J. Pharmacol. Exp. Ther., December 1, 2001; 299(3): 858 - 865. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Z. Dong, M. A. Venkatachalam, J. M. Weinberg, P. Saikumar, and Y. Patel Protection of ATP-Depleted Cells by Impermeant Strychnine Derivatives : Implications for Glycine Cytoprotection Am. J. Pathol., March 1, 2001; 158(3): 1021 - 1028. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. D. Wheeler, M. L. Rose, S. Yamashima, N. Enomoto, V. Seabra, J. Madren, and R. G. Thurman Dietary glycine blunts lung inflammatory cell influx following acute endotoxin Am J Physiol Lung Cell Mol Physiol, August 1, 2000; 279(2): L390 - L398. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
