BIOLOGY
OF
REPRODUCTION
13,
L-Arginine
Stimulation
DAVID Department
of
154-157
of Human
W. KELLER
Obstetrics
and
and
KENNETH
Gynecology, St.
Sperm
Motility
L. POLAKOSKI
Washington
Louis,
in vitro
Missouri
University
School
of
Medicine,
63110
ABSTRACT
semen specimens with low motility were incubated with L-arginmne to determine its effect on sperm motility. Stimulation of forward motility over control values occurred in a dose response relationship, with optimal activity occurring at an L-arginine concentration of 0.004 Al. L-arginine increased the forward motility of sperm at either 23 or 37#{176}C in all samples tested. The increase in forward motility over control values was 81.6 ± 9.96 percent SEM (n=12). The percent stimulation of sperm motility was in general inversely related to the initial semen motility. The physiologically inactive isomer D-arginine. the amino acid L-lysine and the arginine analogs L-homoarginine and L-nitroargmnmne did not stimulate sperm motility. L-ornithine, an arginine metabolite, was also ineffective in stimulating sperm motility. The observation that L-arginine enhances sperm motility in vitro suggests that it may have clinical value when human semen with subnormal motility is utilized for artificial insemination. Human
All thors.
INTRODUCTION
oral
et
Schachter arginine
men
results
in
al. (1973), administration
have reported that to oligospermic
an improvement
in both
temporal sequence of their ment to experiment. Multiple during the same experimental nature of the test compounds examiner.
sperm
count and motility in the majority of individuals treated. In order to evaluate the possible action of arginine upon sperm motility, in vitro studies were that L-arginine sperm
performed.
The
has a specific
motility
in oligospermic
MATERIALS
AND
results
role
The
from
servers from
indicate
Division,
Travenol
Baker’s
of
200
to
buffered
Na2 HPO4 0.01
250
glucose
0.6 g percent;
g percent;
b
-
1)
-
pH
10’
50
M’
solution
were
in place
incubated
3.0 g percent;
to
a final
KH2 P04 concentration of 1 mixtures contained
of the
test compound.
at 37#{176}Cfor one
All specimens
hour
at pH
7.4
prior
to examination.
RESU
X
motility
sperm/mI,
106
to
mens
154
(glucose
NaCI 0.2 g percent;
7.85)
Semen specimens studies exibited sperm
23. 1975. 30, 1974.
saline
sperm/mI. The incubation of diluted semen and an equal volume of reagent dissolved in Baker’s solution. Unless otherwise noted, the final concentration of all test compounds was 0.004 M. Control incubations were performed, utilizing an equal volume of the buffered glucose saline X
8.4 April July
of ob-
where L = individual motility value of each observation in each sample, L = mean motility value of each sample, a = total number of samples evaluated. The semen specimens were diluted in modified
95
Received
both
________
V (a
sperm.
Accepted
variation
for
calculated
S.D.=
A complete semen analysis was performed on each specimen, which included total sperm count, motility, morphology, pH and volume. Oligospermia was defined as less than 50 X iO sperm/mi. Forward motile sperm were defined as those which exhibited forward progression over two 0.005 mm squares in a Neubauer counting chamber. All semen specimens examined exhibited less than 60 percent total initial motility. The percent motility of each specimen was a total
of intra-sample
was
METHODS
Cyclo-Chemical
counting
(S.D.)
examination from expericompounds were tested time period so that the were not obvious to the
the expression
men.
tion.
after
deviation
motility
the auto the
in increasing
Laboratories, Inc. L-nitroarginine was purchased from Eastman Organic Chemicals. L-ornithine hydrochloride was obtained from Sigma Chemicals Company. All other chemicals were reagent grade. After a minimum of 72 h continence, semen specimens were collected in glass vials by masturba-
determined
standard
percent
L-arginine hydrochloride, D-arginine hydrochloride and L-lysine hydrochloride were purchased from Nutritional Biochemicals Corporation. L-homoarginine
was obtained
semen specimens were examined by Samples were randomized in regard
55.2 to
1 x
of
percent.
LTS
used for the counts ranging with Dilution
i07 sperm/mi the specimen,
initial
incubation from 8 to motilities
of
semen
had no effect as compared
of speci-
on the to the
ARGININE
motility
of the undiluted
The standard tion of percent ously)
was
Dose
on
the
basis
are
creased
was
trations. in
general
ty
at higher
The
occurred
of to
the
lowest
represented
specimens percent,
with initial motilities represented by closed respectively,
creases
higher
percent
over
L-arginine.
lyzed test.
the at
levels
in forward relative
sperm to
motil-
the
initial
data
motility
The
The vitro
to
significant
time was
experiments, decrease
t
a
sperm moIn ten of
motility
of
incubated
the
L-arginine was greater than the same semen specimen.
the
various on
human
L-arginine
amino
acids
sperm
motility
is illustrated
improvement
and in
in
in sperm
Table
motili-
specimens incubated with (L-homoarginine, D-argiL-lysine or L-ornithine.
course of the also examined. control
to
ana-
the paired resulted in
later
ty was observed in the arginine analogs nine, L-nitroarginine), in
1 were by
1 h
of
analogs
comparison
forward
of
effect
arginine
of
Table
the
specimen
sperm
concentration
M
in percent (P
OF
REPRODUCTION
13,
L-Arginine
Stimulation
DAVID Department
of
154-157
of Human
W. KELLER
Obstetrics
and
and
KENNETH
Gynecology, St.
Sperm
Motility
L. POLAKOSKI
Washington
Louis,
in vitro
Missouri
University
School
of
Medicine,
63110
ABSTRACT
semen specimens with low motility were incubated with L-arginmne to determine its effect on sperm motility. Stimulation of forward motility over control values occurred in a dose response relationship, with optimal activity occurring at an L-arginine concentration of 0.004 Al. L-arginine increased the forward motility of sperm at either 23 or 37#{176}C in all samples tested. The increase in forward motility over control values was 81.6 ± 9.96 percent SEM (n=12). The percent stimulation of sperm motility was in general inversely related to the initial semen motility. The physiologically inactive isomer D-arginine. the amino acid L-lysine and the arginine analogs L-homoarginine and L-nitroargmnmne did not stimulate sperm motility. L-ornithine, an arginine metabolite, was also ineffective in stimulating sperm motility. The observation that L-arginine enhances sperm motility in vitro suggests that it may have clinical value when human semen with subnormal motility is utilized for artificial insemination. Human
All thors.
INTRODUCTION
oral
et
Schachter arginine
men
results
in
al. (1973), administration
have reported that to oligospermic
an improvement
in both
temporal sequence of their ment to experiment. Multiple during the same experimental nature of the test compounds examiner.
sperm
count and motility in the majority of individuals treated. In order to evaluate the possible action of arginine upon sperm motility, in vitro studies were that L-arginine sperm
performed.
The
has a specific
motility
in oligospermic
MATERIALS
AND
results
role
The
from
servers from
indicate
Division,
Travenol
Baker’s
of
200
to
buffered
Na2 HPO4 0.01
250
glucose
0.6 g percent;
g percent;
b
-
1)
-
pH
10’
50
M’
solution
were
in place
incubated
3.0 g percent;
to
a final
KH2 P04 concentration of 1 mixtures contained
of the
test compound.
at 37#{176}Cfor one
All specimens
hour
at pH
7.4
prior
to examination.
RESU
X
motility
sperm/mI,
106
to
mens
154
(glucose
NaCI 0.2 g percent;
7.85)
Semen specimens studies exibited sperm
23. 1975. 30, 1974.
saline
sperm/mI. The incubation of diluted semen and an equal volume of reagent dissolved in Baker’s solution. Unless otherwise noted, the final concentration of all test compounds was 0.004 M. Control incubations were performed, utilizing an equal volume of the buffered glucose saline X
8.4 April July
of ob-
where L = individual motility value of each observation in each sample, L = mean motility value of each sample, a = total number of samples evaluated. The semen specimens were diluted in modified
95
Received
both
________
V (a
sperm.
Accepted
variation
for
calculated
S.D.=
A complete semen analysis was performed on each specimen, which included total sperm count, motility, morphology, pH and volume. Oligospermia was defined as less than 50 X iO sperm/mi. Forward motile sperm were defined as those which exhibited forward progression over two 0.005 mm squares in a Neubauer counting chamber. All semen specimens examined exhibited less than 60 percent total initial motility. The percent motility of each specimen was a total
of intra-sample
was
METHODS
Cyclo-Chemical
counting
(S.D.)
examination from expericompounds were tested time period so that the were not obvious to the
the expression
men.
tion.
after
deviation
motility
the auto the
in increasing
Laboratories, Inc. L-nitroarginine was purchased from Eastman Organic Chemicals. L-ornithine hydrochloride was obtained from Sigma Chemicals Company. All other chemicals were reagent grade. After a minimum of 72 h continence, semen specimens were collected in glass vials by masturba-
determined
standard
percent
L-arginine hydrochloride, D-arginine hydrochloride and L-lysine hydrochloride were purchased from Nutritional Biochemicals Corporation. L-homoarginine
was obtained
semen specimens were examined by Samples were randomized in regard
55.2 to
1 x
of
percent.
LTS
used for the counts ranging with Dilution
i07 sperm/mi the specimen,
initial
incubation from 8 to motilities
of
semen
had no effect as compared
of speci-
on the to the
ARGININE
motility
of the undiluted
The standard tion of percent ously)
was
Dose
on
the
basis
are
creased
was
trations. in
general
ty
at higher
The
occurred
of to
the
lowest
represented
specimens percent,
with initial motilities represented by closed respectively,
creases
higher
percent
over
L-arginine.
lyzed test.
the at
levels
in forward relative
sperm to
motil-
the
initial
data
motility
The
The vitro
to
significant
time was
experiments, decrease
t
a
sperm moIn ten of
motility
of
incubated
the
L-arginine was greater than the same semen specimen.
the
various on
human
L-arginine
amino
acids
sperm
motility
is illustrated
improvement
and in
in
in sperm
Table
motili-
specimens incubated with (L-homoarginine, D-argiL-lysine or L-ornithine.
course of the also examined. control
to
ana-
the paired resulted in
later
ty was observed in the arginine analogs nine, L-nitroarginine), in
1 were by
1 h
of
analogs
comparison
forward
of
effect
arginine
of
Table
the
specimen
sperm
concentration
M
in percent (P
