Bioavailability of griseofulvin from tablets in beagle dogs and correlation with dissolution rate and bioavailability in humans


Aoyagi, N.; Ogata, H.; Kaniwa, N.; Koibuchi, M.; Shibazaki, T.; Ejima, A.; Tamaki, N.; Kamimura, H.; Katougi, Y.; Omi, Y.

Journal of Pharmaceutical Sciences 71(10): 1169-1172

1982


The bioavailability of four griseofulvin tablets in beagle dogs, including an ultramicrosize tablet used previously in a human bioavailability study, was investigated on the basis of the plasma 6-demethyl-griseofulvin concentration. The relations with the in vivo findings in humans and the in vitro dissolution rates also were examined. Contrary to the lower bioavailability of the ultramicrosize formulation in humans, it provided the best bioavailability in beagles. The microsize griseofulvin formulations showed similar in vivo results to those in humans. Poor correlation of in vivo parameters between humans and beagles was attributed to the discrepancy of the availability of the ultramicrosize formulation between the two species. The dissolution rates determined by the pretreatment method using plastic beads were correlated more with the in vivo findings than those determined by the other methods. Beagles were a useful animal model for bioavailability studies of certain griseofulvin formulations but not ultramicrosize ones.

(5)
M.
Kraml,
J.
Dubuc,
and
D.
Dvornik,
Arch.
Dermatol.,
87,
179
(1963).
(6)
J.
R.
Marvel,
D.
A.
Schlichting,
D.
Denton,
E.
J.
Levy,
and
M. M.
Cahn,
J.
Invest.
Dermatol.,
42,
197
(1964).
(7)
B.
Katchen
and
S.
Symchowicz,
J.
Pharm.
Sci.,
56,
1108
(1967).
(8)
S.
Symchowicz
and
B.
Katchen,
ibid.,
57,
1383
(1968).
(9)
S.
Lin,
J.
Menig,
and
L.
Lachman,
ibid.,
57,
2143
(1968).
(10)
W.
L.
Chiou
and
S.
Riegelman,
ibid.,
60,
1376 (1971).
(11)
W.
E.
Barrett,
Curr.
Ther.
Res.,
18,
501
(1975).
(12)
Ibid.,
18,
491
(1975).
(13)
A.
B.
Straughn,
M.
C.
Meyer,
G.
Raghow,
and
K.
Rotenberg,
J.
Pharmacokinet.
Biopharm.,
8,
347
(1980).
(14)
J.
G.
Wagner,
"Fundamentals
of
Clinical
Pharmacokinetics,"
Drug
Intelligence
Publications,
Hamilton,
Ill.,
1975,
p.
344.
(15)
H.
J.
Schwarz,
B.
A.
Waldman,
and
V.
Madrid,
J.
Pharm.
Sci.,
65,
370
(1976).
(16)
"USP
Pharmacopeial
Forum,"
3,
22-25
(1977).
(17)
H.
Ogata,
T.
Shibazaki,
T.
Inoue,
and
A.
Ejima,
J.
Pharm.
Sci.,
68,
712
(1979).
(18)
G.
Levy,
ibid.,
50,
388
(1961).
(19)
Ibid.,
52,
1039
(1963).
Bioavailability
of
Griseofulvin
from
Tablets
in
Beagle
Dogs
and
Correlation
with
Dissolution
Rate
and
Bioavailability
in
Humans
NOBUO
AOYAGI
*x,
HIROYASU
OGATA
*,
NAHOKO
KANIWA
*,
MASANOBU
KOIBUCHI
*t,
TOSHIO
SHIBAZAKI
*,
AKIRA
EJIMA
*,
NORIYASU
TAMAKI
t,
HIDETAKA
KAMIMURA
§,
YOSHIO
KATOUGI
t,
and
YUKIO
OMI
Received
July
31,
1981,
from
the
*Division
of
Drugs,
National
Institute
of
Hygienic
Sciences,
18-1,
Kamiyoga
1-chome
,
Setagaya-ku,
Tokyo
158,
Japan;
the
t
Yaizu
Plant,
Yamanouchi
Pharmaceutical
Co.
Ltd.,
Ozumi-180,
Yaizu-shi,
Shizuoka
-ken
425,
Japan;
and
the
§Institute
of
Research
and
Development,
Yamanouchi
Pharmaceutical
Co.
Ltd.,
1-8,
Azusawa
1-chome,
Itabashi-ku,
Tokyo
174,
Japan.
/Deceased.
Accepted
for
publication
December
30,
1981.
Abstract
0
The
bioavailability
of
four
griseofulvin
tablets
in
beagle
dogs,
including
an
ultramicrosize
tablet
used
previously
in
a
human
bioavail-
ability
study,
was
investigated
on
the
basis
of
the
plasma
6-demethyl-
griseofulvin
concentration.
The
relations
with
the
in
vivo
findings
in
humans
and
the
in
vitro
dissolution
rates
also
were
examined.
Contrary
to
the
lower
bioavailability
of
the
ultramicrosize
formulation
in
humans,
it
provided
the
best
bioavailability
in
beagles.
The
microsize
griseofulvin
formulations
showed
similar
in
vivo
results
to
those
in
humans.
Poor
correlation
of
in
vivo
parameters
between
humans
and
beagles
was
at-
tributed
to
the
discrepancy
of
the
availability
of
the
ultramicrosize
for-
mulation
between
the
two
species.
The
dissolution
rates
determined
by
the
pretreatment
method
using
plastic
beads
were
correlated
more
with
the
in
vivo
findings
than
those
determined
by
the
other
methods.
Beagles
were
a
useful
animal
model
for
bioavailability
studies
of
certain
griseof-
ulvin
formulations
but
not
ultramicrosize
ones.
Keyphrases
0
Bioavailability—griseofulvin
from
tablets
in
beagle
dogs,
correlation
with
dissolution
rate
and
bioavailability
in
humans
0
Dis-
solution
rates—bioavailability
of
griseofulvin
from
tablets
in
beagle
dogs,
bioavailability
in
humans
0
Griseofulvin—bioavailability
from
tablets
in
beagle
dogs,
dissolution
rate
and
bioavailability
in
humans
The
bioavailabilities
for
four
lots
of
griseofulvin
tablets
in
humans
have
been
reported
previously,
and
the
relations
with
in
vitro
dissolution
rates
have
been
discussed
(1).
Beagle
dogs
are
often
used
as
an
animal
model
for
bio-
availability
studies,
but
their
suitability
has
not
been
clarified
sufficiently.
A
good
relation
of
penicillin
bio-
availability
between
humans
and
dogs
was
reported
(2).
Previous
studies
on
bioavailability
of
diazepam
formula-
tions
in
humans
and
beagles
revealed
no
good
relations
between
the
results
from
both
species.
The
discrepancy
was
considered
to
be
due
to
the
differences
of
physiological
states
of
the
GI
tract,
especially
of
gastric
emptying
rate
and
GI
transition
time
(3).
In
the
present
study
the
bioavailability
of
griseofulvin
from
tablets
in
beagles
was
studied,
and
the
relations
with
in
vivo
results
in
humans
and
in
vitro
dissolution
rates
were
investigated.
EXPERIMENTAL
Formulations
—Four
lots
of
tablets
containing
125
mg
of
griseofulvin
employed
in
the
human
bioavailability
study
(1)
were
used.
One
formu-
30
10
I
le
/
/
/
/
/0
--o
125
250
DOSE,
mg
Figure
1
—Relation
between
griseofulvin
dose
and
AUC.,
of
6-dem-
ethylgriseofulvin. Key:
(-
-
-)
responses
of
the
individual
dogs;
(—)
average
response.
0022-3549/
82/
01000-1169$01.00/
0
©
1982,
American
Pharmaceutical
Association
Journal
of
Pharmaceutical
Sciences
/
1169
Vol.
71,
No.
10,
October
1982
Table
I
-Plasma
Concentrations
of
Griseofulvin
and
6-Demethylgriseofulvin
Following
Oral
Administration
of
Formulation
A
to
12
Beagles
Griseofulvin
6-Demethylgriseofulvin
In
Viuo
Parameter
Means
±
SD
Coefficient
of
Variation,
Means
±
SD
Coefficient
of
Variation,
Plasma
Concentration
µg/m1
0.5
hr
1
2
3
4
6
8
10
24
C
max,
µg/m1
0.209
±
0.202
0.494
f
0.481
0.429
±
0.298
0.327
±
0.196
0.203
±
0.116
0.103
f
0.036
0.065
f
0.033
0.050
f
0.036
0.003
±
0.010
0.626
f
0.458
97
97
70
60
57
35
51
73
333
73
1.559
±
1.128
2.562
±
1.264
2.059
±
1.138
1.519
±
0.763
1.092
±
0.468
0.843
±
0.259
0.753
f
0.298
0.544
±
0.289
0.127
±
0.199
3.083
f
1.114
72
49
55
50
43
31
40
53
157
36
Table
II
-Plasma
Levels,
C
MAX,
t
max,
and
A
UC
24
of
6-Demethylgriseofulvin
Following
Oral
Administration
of
Four
Lots
of
125
-mg
Griseofulvin
Tablets
to
Beagles
in
Viuo
Parameter
Formulation"
Result
b
of
ANOVA
Tukey's
Test
A
Plasma
0.5
hr
level,
1.559
±
0.325
1.265
±
0.290
0.640
±
0.123
0.699
±
0.229
p
<
0.05
A>B>D>C
µg/ml
1
2.562
±
0.365
1.857
±
0.342
0.925
±
0.112
1.222
±
0.272
p
<
0.01
A>B>D>C
2
2.059
±
0.329
1.482
1
0.314
0.977
±
0.135
1.234
1
0.105
p
<
0.01
A>B>D>C
3
1.519
±
0.220
1.170
1
0.256
0.850
1
0.138
0.951
±
0.093
p
<
0.05
A>B>D>C
4
1.092
±
0.135
0.924
±
0.199
0.845
±
0.202
0.813
±
0.136
NS
6
0.843
1
0.075
0.714
±
0.135
0.540
±
0.101
0.540
±
0.098
NS
8
0.753
1
0.086
0.584
1
0.110
0.434
1
0.086
0.483
±
0.081
NS
10
0.544
1
0.083
0.463
1
0.102
0.282
±
0.040
0.442
±
0.102
NS
24
0.127
+
0.057
0.071
±
0.017
0.077
1
0.029
0.053
±
0.015
NS
C
m
.,
µg/m1
3.083
±
0.321
2.340
±
0.322
1.369
1
0.156
1.749
1
0.190
p
<
0.01
A>B>D>C
t
m
.,
hr
1.5
±
0.2
1.3
±
0.2
1.9
±
0.5
1.7
±
0.3
NS
A
UC
24
,
µg
hr/ml
16.34
1
1.38
12.86
±
2.77
8.86
±
1.05
10.62
1
1.48
<
0.01
A>B>D>C
The
figures
indicate
means
±
standard
error.
b
NS:
not
significant.
Formulations
underlined
by
a
common
line
did
not
differ
significantly
(p
<
0.05).
lation
was
an
ultramicrosize
griseofulvin
tablet
(A);
the
others
were
commercial
microsize
griseofulvin
tablets
(B,
C,
D).
Dissolution
Rate
-The
methods
to
determine
the
dissolution
rates
were
carried
out
as
reported
previously
(1).
Sink
methods
included
nonpretreatment
(18
-liter
beaker
method
and
basket
method)
and
pre-
treatment
(Methods
I
and
II).
The
dissolution
rate
was
expressed
as
t30
the
time
taken
for
30%
of
the
drug
to
dissolve.
Bioavailability-Twelve
beagles
(12.0-14.0
kg;
mean
12.9)
were
randomly
divided
into
four
groups
according
to
a
Latin
square
crossover
design.
The
beagles,
having
fasted
for
20
hr,
were
given
a
test
tablet
and
then
forced
to
take
30
ml
of
water.
The
beagles
were
not
given
any
food
until
10
hr
after
drug
administration.
Blood
samples
were
taken
at
0.5,
1,
2,
3,
4,
6,
8,
10,
and
24
hr
after
administration,
and
the
plasma
samples
were
frozen
and
stored
until
assay.
The
experiments
were
repeated
every
3
E
rn
2
2
-J
g
1
a_
5
10
24
HOURS
Figure
2
-Mean
plasma
6-demethylgriseofulvin
concentration
after
oral
administration
of
125
-mg
griseofulvin
formulations
to
beagles.
Key:
(•)
Tablet
A;
(0)
Tablet
B;
A)
Tablet
C;
(0)
Tablet
D.
The
vertical
lines
show
standard
errors.
week
according
to
the
dosage
schedule.
The
bioavailability
for
each
for-
mulation
was
evaluated
from
the
plasma
concentrations
of
6-demethyl-
griseofulvin,
a
metabolite
of
griseofulvin,
at
each
sampling
time,
peak
plasma
concentration
(C.),
time
to
Cmax
ftmax,
1,
and
area
under
plasma
concentration
-time
curves
from
0
to
the
sampling
time
t
(AUC
t
).
The
value
for
AUC-
was
calculated
by
the
method
of
Wagner
(4).
HUMANS,
Cmax•
g9/m1
0.7
0.6
0.5
0.4
C
B
A
2
3
BEAGLES,
C
max
,
µg/m1
Figure
3
-Correlation
of
C„,
ar
values
after
oral
administration
of
four
griseofulvin
formulations
between
humans
and
beagles.
1170
/
Journal
of
Pharmaceutical
Sciences
Vol.
71,
No.
10,
October
1982
TableIII-Cmax,
tmax,
and
AUC24
of
6-Demethylgriseofulvin
Following
Oral
Administration
of
Three
Griseofulvin
Formulations
a
24
23
8
Parameter
Formu-
lation
Volume
of
Water
Paired"
t
test
30
ml
200
ml
C
max
,
µg/ml
A
3.038
±
0.287'
2.608
±
0.167
NS
.0
B
2.290
±
0.490
2.067
±
0.160
NS
0
6
D
1.787
±
0.270
1.388
±
0.381
NS
....'
t
max,
hr
A
1.6
±
0.2
1.8
±
0.2
NS
B
1.2
±
0.2
1.7
±
0.4
NS
4
D
1.9
1
0.4
3.6
±
1.0
NS
AUC24,
Ag
hr/ml
A
18.89
±
1.15
17.59
±
0.88
NS
B
11.13
±
2.56
14.46
±
1.79
NS
2
D
11.68
±
2.10
11.50
±
1.96
NS
With
30
and
200
ml
of
water.
b
NS:
not
significant.
Mean
4
standard
error.
Dose-AUG.
Relation
-Three
beagles
were
fasted
overnight
and
given
one
and
two
tablets
of
Formulation
C,
corresponding
to
125
and
250
mg
of
griseofulvin,
respectively.
The
other
procedures
were
the
same
as
described
for
the
bioavailability
test.
Effects
of
Volume
of
Water
Coadministered-Three
formulations,
including
the
ultramicrosize
formulation,
were
used.
Eight
beagles
were
given
a
tablet
with
30
and
200
ml
of
water
in
a
crossover
design.
The
other
procedures
were
the
same
as
described
for
the
bioavailability
test.
Assay-Griseofulvin
and
6-demethylgriseofulvin
in
plasma
were
de-
termined
by
GC
(5).
RESULTS
Plasma
Levels
of
Griseofulvin
and
6-Demethylgriseofulvin-
Table
I
shows
the
mean
plasma
griseofulvin
and
6-demethylgriseofulvin
concentrations
after
oral
administration
of
Formulation
A.
The
plasma
griseofulvin
concentrations
were
below
one
-fifth
of
those
of
6-demeth-
ylgriseofulvin,
and
only
a
trace
of
griseofulvin
was
detected
at
24
hr
after
administration
of
the
drug.
This
can
be
attributed
to
the
greater
clearance
of
griseofulvin
in
dogs
than
in
humans
(6,
7),
and
hence,
a
considerable
fraction
of
the
dose
administered
orally
will
be
converted
to
6-demeth-
ylgriseofulvin
by
first
-pass
metabolism
before
reaching
the
blood
circu-
lation
(8).
The
great
clearance
of
griseofulvin
probably
leads
to
the
greater
coefficients
of
variation
found
in
the
plasma
levels
of
griseofulvin
than
those
of
6-demethylgriseofulvin.
Considering
the
findings,
the
bioavail-
ability
of
griseofulvin
in
beagles
was
estimated
on
the
basis
of
the
plasma
level
of
6-demethylgriseofulvin.
Bioavailability-The
relation
of
the
griseofulvin
dose
and
the
A
UC.,
of
6-demethylgriseofulvin
is
shown
in
Fig.
1.
Large
differences
in
the
AUCm
values
among
the
beagles
were
found.
With
the
high
dose,
the
unabsorbed
fraction
of
the
drug
may
increase
by
being
not
fully
dissolved
in
the
GI
tract.
Figure
2
shows
the
mean
plasma
level
-time
curves
of
6-demethyl-
griseofulvin
following
oral
administration
of
four
formulations.
Table
II
lists
their
mean
values
for
in
vivo
parameters.
The
plasma
levels
of
6-demethylgriseofulvin
at
24
hr
were
very
low,
so
the
AUC
24
can
be
considered
as
AUC-.
Although
the
ultramicrosize
formulation
(A)
showed
relatively
low
bioavailability
in
humans
(1),
this
formulation
showed
the
highest
values
in
the
plasma
concentrations,
C.
and
AUC24,
in
beagles.
The
ratios
of
C.
and
AUC
24
of
the
ultramicrosize
formu-
lation
to
those
of
Formulation
B,
which
showed
the
highest
availability
of
all
microsize
formulations,
were
132
and
127%,
respectively.
Significant
differences
were
found
between
Formulation
A
and
two
microsize
for-
mulations
(C
and
D)
in
the
plasma
levels
at
earlier
sampling
times,
C.
and
A
UC24.
000
00
00
00110
itt•
00
00
000
ONO
811
OD
ISM
00
0000
Human
Beagle
Human
Beagle
Human
Beagle
Human
Beagle
TABLET
A
TABLET
B
TABLET
C
TABLET
D
Figure
4
-Individual
t
max
values
in
beagles
and
humans
after
oral
administration
of
four
griseofulvin
formulations.
For
microsize
formulations,
the
in
vivo
results
were
similar
to
those
in
humans:
Formulation
B
had
the
best
bioavailability
as
expected
from
the
in
vitro
dissolution
rate
and
Formulation
D
showed
better
bioavail-
ability
than
Formulation
C.
A
significant
difference
was
found
in
C.
between
Formulations
B
and
C
but
not
in
plasma
levels
and
AUC24.
The
tmax
values
in
beagles,
which
seemed
shorter
than
those
in
humans
(3.6-7.9
hr),
did
not
show
significant
differences
among
the
formula-
tions.
Effects
of
Volume
of
Water
Coadministered-Thirty
milliliters
of
water
was
given
to
beagles;
however,
200
ml
was
used
in
the
human
bioavailability
study
(1).
The
large
volume
of
water
enhanced
the
in
vivo
absorption
of
erythromycin
stearate
and
amoxicillin
which
are
poorly
soluble
in
water
(9).
The
different
volumes
of
water
used
in
the
human
and
beagle
tests
might
lead
to
a
discrepancy
in
the
in
vivo
results,
espe-
cially
for
the
ultramicrosize
formulation.
To
clarify
this,
the
bioavaila-
bilities
were
tested
with
30
and
200
ml
of
water.
As
shown
in
Table
HI,
the
fl
uid
volume
did
not
significantly
affect
the
bioavailabilities,
which
leads
to
the
conclusion
that
the
discrepancy
of
bioavailabilities
between
humans
and
beagles
is
not
due
to
the
difference
of
the
volume
of
water
administered.
As
another
explanation,
the
physiological
differences
in
the
GI
tract
between
the
two
species
may
be
considered.
Correlation
Between
the
Bioavailability
and
Dissolution
Rates
-The
correlation
coefficients
between
the
in
vivo
parameters
and
in
vitro
dissolution
rates
(t
30
)
determined
by
sink
methods
are
shown
in
Table
IV.
The
in
vivo
parameters
are
correlated
more
in
the
log
-log
and
normal
-reciprocal
regressions
with
tao
determined
by
Method
II
(Table
IV),
in
which
the
tablets
were
treated
in
20
ml
of
water
with
plastic
beads
before
the
determination
of
dissolution
rates.
Correlation
Between
Humans
and
Beagles
-As
shown
in
Table
V,
low
correlation
coefficients
were
found
between
humans
and
beagles.
The
poor
relations
are
attributed
mainly
to
the
discrepancy
of
the
ul-
tramicrosize
formulation
(A)
between
them.
Figure
3
shows
that
the
microsize
formulations
(B,
C,
D)
showed
a
good
relation
(r
=
0.976)
in
C
max
values
between
humans
and
beagles,
which
suggests
that
the
bioavailabilities
of
microsize
formulations
can
be
evaluated
in
beagles
instead
of
humans.
DISCUSSION
The
in
vivo
findings
in
beagles
did
not
correlate
well
with
those
in
humans.
The
ultramicrosize
formulation
provided
the
best
availability
Table
IV
-Correlation
Coefficients
Between
In
Vivo
Parameters
(X)
and
t
30
(Y)
Determined
by
Sink
Methods
In
Vitro
Test
X
-
Y
-1
log
X
-
log
Y
Serum
Level
AUC
24
Serum
Level
Cmax
AUC
24
Method
Condition
1
hr
3
hr
5
hr
1
hr
3
hr
5
hr
Beaker
0.747
0.631
0.514
0.613
0.579
-0.872
-0.760
-0.655
-0.731
-0.701
Polysorbate
80
0.714
0.595
0.474
0.577
0.541
-0.859
-0.748
-0.638
-0.719
-0.686
Diastase
0.776
0.672
0.562
0.658
0.625
-0.916
-0.846
-0.751
-0.824
-0.793
848
rpm
0.803
0.697 0.587
0.680
0.648
-0.903
-0.802
-0.704
-0.775
-0.747
pH
1.2
0.556
0.423
0.292
0.405
0.366
-0.788
-0.656
-0.535
-0.623
-0.587
pH
1.2
Polysorbate
80
0.641
0.510
0.382
0.491
0.453
-0.793
-0.663
-0.542
-0.630
-0.594
Basket
-
0.872
0.790
0.695
0.777
0.749
-0.948
-0.896
-0.815
-0.878
-0.851
Method
I
-
0.472
0.422
0.341
0.429
0.404
-0.589
-0.636
-0.575
-0.635
-0.602
Method
II
-
0.943
0.932
0.889
0.933
0.903
-0.910
-0.945
-0.910
-0.943
-0.927
Journal
of
Pharmaceutical
Sciences
/
1171
Vol.
71,
No.
10,
October
1982
Table
V
—Correlation
Coefficients
of
Bioavailability
Parameters
Between
Humans
and
Beagles
Beagle
Human
C0.5
°
C
C
max
t
max
AUC24
Cl
C3
C
C3
C
max
t
max
A
UC47.5
0.789
0.505
0.678
0.448
0.388
0.711
0.306
°
C
t
shows
the
plasma
or
serum
concentration
at
time
t.
in
beagles
contrary
to
its
lower
absorption
in
humans.
Considering
the
insignificant
effects
of
the
volume
of
water
on
the
bioavailability,
the
ultramicrosize
formulation
discrepancy
may
be
attributed
to
the
physi-
ological
differences
in
the
GI
tract.
None
of
the
in
vitro
dissolution
methods
indicated
such
a
superiority
of
the
ultramicrosize
formulation
in
beagles.
These
findings
suggest
that
this
formulation
may
disintegrate
into
the
original
ultramicrosize
particulate
state
of
the
drug
and
allow
rapid
dissolution
in
the
GI
tract
in
beagles
beyond
the
expectation
from
the
in
vitro
dissolution
findings.
Thel
ma)
,
values
in
beagles
for
different
formulations
were
smaller
than
those
in
humans
(Fig.
4).
This
suggests
rapid
transition
of
the
drug
to
the
absorption
site,
namely,
fast
gastric
emptying
of
the
drug
in
beagles.
The
good
bioavailability
of
the
ultramicrosize
formulation
may
be
related
to
the
rapid
gastric
emptying
of
the
drug
which
leads
to
dissolution
of
the
drug
in
the
small
intestinal
tract.
Formulation
D
provided
higher
C
m
ax
and
plasma
levels
at
earlier
sampling
times
than
Formulation
C
as
observed
in
the
human
test.
The
in
vitro
dissolution
rate
of
the
drug
from
Formulation
D
was
enhanced
over
that
from
Formulation
C
by
pretreatment
with
plastic
beads.
These
NOTES
findings
suggest
that
in
beagles
and
humans
there
is
a
strong
intensive
deaggregation
action
on
the
particles
or
aggregates
of
the
drug
during
their
transition
into
the
GI
tract.
Although
there
was
no
significant
difference
in
AUG.
values
among
the
formulations
in
humans,
the
AUC
24
(considered
as
AUC.)
of
For-
mulations
C
and
D
were
significantly
lower
than
that
of
Formulation
A
in
beagles.
This
suggests
their
incomplete
dissolution
during
passage
through
the
GI
tract
and
also
suggests
the
short
absorption
site
and/or
fast
transition
of
the
drug
in
the
GI
tract
in
beagles
as
previously
shown
for
the
bioavailability
of
diazepam
in
beagles
(3).
Although
the
in
vivo
findings
of
the
ultramicrosize
formulation
in
beagles
did
not
agree
with
those
in
humans,
the
bioavailabilities
of
the
microsize
formulations
showed
good
agreement.
Considering
this,
beagles
may
serve
as
a
useful
animal
model
for
bioavailability
studies
of
certain
griseofulvin
tablet
formulations,
but
not
ultramicrosize
ones.
REFERENCES
(1)
N.
Aoyagi,
H.
Ogata,
N.
Kaniwa,
M.
Koibuchi,
T.
Shibazaki,
and
A.
Ejima,
J.
Pharm.
Sci.,
71,
1165
(1982).
(2)
J.
W.
Poole,
Rev.
Can.
Biol.
Suppl.,
32,
43
(1973).
(3)
H.
Ogata,
N.
Aoyagi,
N.
Kaniwa,
M.
Koibuchi,
T.
Shibazaki,
A.
Ejima,
T.
Shimamoto,
T.
Yashiki,
Y.
Ogawa,
Y.
Uda,
and
Y.
Nishida,
Int.
J.
Glin.
Pharmacol.
Toxicol.,
in
press.
(4)
J.
G.
Wagner,
"Fundamentals
of
Clinical
Pharmacokinetics,"
Drug
Intelligence
Publications,
Hamilton,
III.,
1975,
p.
344.
(5)
H.
Kamimura,
Y.
Omi,
Y.
Shiobara,
N.
Tamaki,
and
Y.
Katogi,
J.
Chromatogr.,
163,
271
(1979).
(6)
M.
Rowland,
S.
Riegelman,
and
W.
L.
Epstein,
J.
Pharm.
Sci.,
57,
984
(1968).
(7)
P.
A.
Harris
and
S.
Riegelman,
ibid.,
58,
93
(1969).
(8)
W.
L.
Chiou
and
S.
Riegelman,
ibid.,
59,
937
(1970).
(9)
P.
G.
Welling,
Pharm.
Int.,
1,
14
(1980).
Antibradykinin
Active
Material
in
Aloe
saponaria
AKIRA
YAGI
*x,
NOBUO
HARADA
t,
HIDENORI
YAMADA
*,
SHUICHI
IWADARE
t,
and
ITSUO
NISHIOKA
*
Received
October
27,
1981,
from
the
*Faculty
of
Pharmaceutical
Sciences,
Kyushu
University,
Maidashi,
Higashi-ku,
Fukuoka,
Japan,
and
the
1
Banyu
Pharmaceutical
Co.
,
Ltd.,
Nihonbashi
honcho,
Chuo-ku,
Tokyo,
Japan.
Accepted
for
publication
December
31,
1981.
Abstract
12A
material
having
antibradykinin
activity
on
isolated
guinea
pig
ileum
was
partially
purified
from
the
nondialysate
of
the
pulp
of
Aloe
saponaria
by
repetition
of
gel
chromatography
using
a
hydrophilic
polyvinyl
gel
and
dextran
gels.
From
the
results
of
amino
acid
and
car-
bohydrate
analyses,
the
antibradykinin-active
material
was
estimated
to
be
a
glycoprotein.
It
was
found
that
this
material
catalyzes
the
hy-
drolysis
of
bradykinin
at
pH
7.4.
The
results
of
peptide
analysis
using
reversed
-phase
high-performance liquid
chromatography
coupled
with
amino
acid
analysis
indicate
that
this
glycoprotein
cleaves
the
Gly
4
-Phe
5
and
Pro?-Phes
bonds
of
the
bradykinin
molecule.
Keyphrases
®Antibradykinin—active
material
in
Aloe
saponaria,
guinea
pig
ileum,
glycoprotein,
high-performance
liquid
chromatography
Glycoprotein—antibradykinin
active
material
in
Aloe
saponaria,
high-performance liquid
chromatography,
guinea
pig
ileum
CU
Aloe
sa-
ponaria—antibradykinin
active
material,
glycoprotein,
high-performance
liquid
chromatography,
guinea
pig
ileum
Cardiac
stimulant
action
of
the
constituents
in
the
di-
alysate
of
the
pulp
from
Aloe
saponaria
1
on
isolated
car
-
I
Aloe
saponaria
is
also
known
as
white
spotted
aloe
or
soap
aloe.
diac
muscles
has
been
reported
(1).
Antibradykinin
ac-
tivity
of
the
nondialysate
of
the
pulp
has
been
examined
here
to
obtain
pharmacological
evidence
for
its
anti-in-
fl
ammatory
action
(2).
In
this
report,
the
results
of
partial
purification
of
material
having
antibradykinin
activity
from
A.
saponaria
on
isolated
guinea
pig
ileum
and
its
proteolytic
property
against
bradykinin
are
presented.
EXPERIMENTAL
Materials
—The
following
materials
were
purchased
from
suppliers:
dextran
gel
23
,
hydrophilic
polyvinyl
ge1
4
,
dialysis
membranes,
synthetic
bradykinin
6
,
and
bromelain
7
.
The
gel
filtrations
were
performed
at
room
temperature
at
a
flow
rate
of
21
ml/hr
using
a
microtube
pumps.
Methods
of
Analysis
—Protein
and
carbohydrate
contents
in
samples
2
Sephadex
G-100,
Pharmacia
Fine
Chemicals,
Uppsala,
Sweden.
3
Sephadex
G-25,
Pharmacia
Fine
Chemicals,
Uppsala,
Sweden.
4
Toyopearl
HW
40,
Toyo
Soda
Mfg.,
Co.
Ltd.,
Tokyo,
Japan.
5
Visking
tube,
Visking
Co.,
Union
Carbide
Corp.
6
The
Protein
Research
Foundation,
Osaka,
Japan.
7
Nakarai
Chemical
Co.,
Ltd.,
Kyoto,
Japan.
8
Tokyo
Riakkikai
Co.,
Ltd.,
Tokyo,
Japan.
1172
/
Journal
of
Pharmaceutical
Sciences
0022-3549/82/
01000-1172$01.00/
0
Vol.
71,
No.
10,
October
1982
©
1982,
American
Pharmaceutical
Association