BIOLOGY
OF
REPRODUCTION
18,
Target
639-642
Organs
Artery
for
(1978)
Testosterone
Transferred
in the Pampiniform
MICHAEL
J. FREE
Plexus:
and
Biology
Batelle,
from
The
RICHARD
Vein
to
Epididymis
A, JAFFE
Department,
Pacific
Northwest
Rich/and,
WA
Laboratories,
99352
ABSTRACT
During
infusion
of
testosterone-3
H into
the
pampiniform
plexus
of 8 anesthetized
rats,
radioactivity
in
blood
from
the testicular
artery
was more
than
4 times
that
in systemic
arterial
blood.
During
the same
infusion
period,
radioactivity
in epididymal
artery
blood
remained
similar
to systemic
artery
blood
levels.
Endogenous
testosterone
levels
in epididymal
artery
blood
from
9
additional
rats did not differ
from
systemic
artery
blood
levels.
We concluded
that
testosterone
transferred
from
spermatic
vein
to artery
in the pampiniform
plexus
enters
the arterial
supply
distal
to the origin
of the epididymal
arteries
and cannot
therefore
enter
the epididymis
by this
route.
INTRODUCTION
A
the
flux
of
spermatic
vein
strated
in rats
1975),
baboons
and
one
and
et
al.,
of
rats
vein
(Free
Tillson,
1976),
1977),
rams
(Ginther
and
Ganjam,
(Amann
(Dierschke
rabbits
et al.,
to
et
al.,
and
artery
has
1973;
Free
et
al.,
1976),
1975)
and
pigs
men
350-550
and
(Free,
bulls
et al.,
1975).
Since
the
testicle
compared
the
quantity
by
with
interstitium,
one transfer
pendent
ly.
If the
of
this
that
testosterone
elements
of testicular
seems
arterial
between
the
diffusion
iniform
plexus
Target
organs
may
therefore
testicular
ductules.
Accepted
Received
membranes
capsule,
October
July
15,
rete
31,
testis
or
pamp-
capillary
bed.
androgen
fat
pads,
the
into
of
the
rats.
AND
male
METHODS
albino
rats
(body
weight
purchased
was
induced
oxide/oxygen,
maintained
with
open-circuit
administered
by
with
the same
agents
through
halohead
in a
an endo-
throughout
the procedure.
testicular
artery
and collecting
vein
on
the
cranial
pole
of the
testicle
have
been
described
in detail
elsewhere
(Jaffe
and
Free,
1972;
Free
and Jaffe,
1972),
as have the experimental
setups
for studies
of the pampiniform
plexus
in vivo
(Free
and Jaffe,
1975).
In general,
however,
the setup
is a
perfused
in situ pampiniform
plexus
preparation.
The
testicle
is ischemic
and
the testicular
artery
blood
is
diverted
to the
withdrawal
end of an infusion-withdrawal
pump.
The
infusion
end of the same
pump
is
used
to infuse
fresh whole
blood
containing
40-80
ng
(5-12
zCi)/mI
testosterone,
1,2-s H (New
England
Nuclear,
Boston,
MA) through
the testicular
collecting
vein
into
the
pampiniform
plexus.
The
pump
is
calibrated
to deliver
donor
blood
at a rate
(0.32
mI/mm)
within
the
physiologic
range
for rat testes.
During
infusion,
sequential
5-il
blood
samples
were
collected
from
the superior
and/or
inferior
epididymal
Cannulation
has any
likely
to
flow
path
in the
and the testicular
for this short-circuited
be the
epididymis,
monitored
unliketestoster-
one
levels
resulting
from
the transfer
physiologic
significance,
it is most
involve
organs
and
tissues
on the
entery
1973).
Catheters
were
inserted
into
the femoral
artery
and vein and a
testicle
was exposed
through
a mediolateral
scrotal
incision.
Testicular
temperature
was
maintained
between
32.5
and
34#{176}Cby means
of a water-jacketed
saline
bath
while
testicular
and body
temperature
were
a role for venous-arterial
testosterin the maintenance
of androgen-deincrease
anesthetized
closed-circuit
system
administered
tracheal
cannula
(Jaffe
and Free,
reentering
route
is very
small
when
produced
in the testicular
spermatogenic
kg),
Anesthesia
thane/nitrous
enclosure
and
monkeys
(Bayard
the
from
Hilltop
Laboratory
Animals,
Scottsdale,
PA, were
used
for
this
study.
These
rats
were
maintained
in groups
of 2-5
at a
median
temperature
of 22#{176}C, in a 12 h/12
h light/dark
cycle,
in
solid-bottom
plastic
cages
with
Sanicel
(Paxton
Processing
Co., Paxton,
IL) litter.
been
1974),
rhesus
of
Wistar-denived,
Additestoster-
guinea
explored
testosterone
MATERIALS
rams
1973).
endogenous
we
Jaffe,
1976),
Setchell,
transfer
and
study,
epididymides
demon-
Free
Tillson,
and
spermatic
in
been
this
venous-arterial-transferred
between
has
1973;
and
(Jacks
from
artery
(Free
a net
found
testosterone
(Free
wallabies
tionally,
In
radiolabeled
efferent
1977.
1977.
639
of
the
FREE
640
artery
using
to 5-j.d glass
a 30-gauge
micropipette,
hypodermic
inserted
needle
shaft
with
the aid
fused
of an
operating
microscope.
Occasionally,
samples
were taken in a similar
fashion
from
epididymal
and
vasal
veins.
All samples
were
deposited
into glass scintillation
vials containing
0.1
ml water
and, after addition
of 10
ml
Aquasol
(New
England
Nuclear,
Boston,
MA),
assayed
for tnitium
by liquid
scintillation
spectroscopy.
Efficiency
of counting
was determined
by using
toluene-3
H as an internal
standard.
In
a separate
group
of
rats,
maintained
and
anesthetized
under
the conditions
described
previously, a fine
polyethylene
catheter
was inserted
into an
epididymal
artery
1-5
mm distal
to its origin
at the
spermatic
artery.
Blood
samples
(80-120
2l) were
collected
from
these
catherers
while
coincident
samples were
collected
from
the femoral
artery
catheter.
Plasma
prepared
from
these
samples
was assayed
for
testosterone
by radioimmunoassay
procedures
(Resko
et al., 1973).
ET
AL.
into
the
into
the
in
times
those
1A
illustrates
the
of the
of radiolabel
mm)
artery.
The
inferior
artery,
which
5
time
of
mm
infusion
superior
after
20 mm
the
of
the
to
of
a level
femoral
epididymal
spermatic
distal
slightly
contained
remained
the
the
contained
that
of the
branch
from
3
branch,
than
at the
and
artery
H infusion
similar
to
arose
approximately
more
throughout
taken
from
epididymal
1 ,2-
artery
the
superior
higher
levels
(Fig.
1B)
showed
that
1A).
A
similar
of
experiment
radioactivity
artery
similar
entry
(10-12
a rat
infusion
plexus.
were
artery
higher
sample
of
H
pampiniform
artery
systemic
sampling
testosterone
of radioactivity
mal
Figure
the
in
artery
1 ,2-
the
testicular
times
A
branch
femoral
testosterone
of
the
first
3-4
period.
of
veins
Levels
the
and
mm
40
levels
RESULTS
testicular
during
to
(Fig.
in
and
vein
and
those
in
femoral
substantially
lower
than
the
superior
the
epididy-
vasal
artery
those
in
vein
were
blood
and
testicular
E
TIME minI
FIG.
1. Appearance
of
radioactivity
in systemic
and
sterone-1,2-3
H into
the spermatic
veins
of representative
to the corpus
and caput
epididymides.
B. Radioactivity
mides.
TA, testicular
artery;
FA, femoral
artery;
Corpus
Caput
EA, epididymal
artery
on the head of the epididymis.
indicating
the number
of epididymal
arteries
and distance
arrows
indicate
exact
sampling
points
for EA blood.
reproductive
tract
blood
vessels
during
infusion
of testo-
anesthetized
rats. A. Radioactivity
in the blood
supply
in the blood
supply
and drainage
of the caput
epididyEA, epididymal
artery
on the body
of the epididymis;
Inset shows
diagram
of the epididymal
blood
supply
between
their
points
of origin
in the testicular
artery;
TESTOSTERONE
artery
blood.
given
in
of
data
artery,
more
order
to
terone
levels
from
the
for
testosterone.
the
femoral
artery
Under
the
in
enter
the
the
the
enter
arterial
the
± 1.19
Several
supply
infused
into
the
this
did
the
origin
review).
to
tions
were
of
(rat,
rabbit,
arterial
route.
than
in
for
in
the
take
since
it
the
testicular
circulation
This
venous-arterial
place
occurred
in
Free,
the
testosterone
1977
plexus
spermatic
vein
and
testosterone
ping
and
1. Contribution
of
to
labeled
steroid
Values
expressed
as
panipiniform
plexus
cxcontent
of epididymal
percent
of label
in per-
flow
around
elicit
testicular
FA
Corpus
EA
TA
Large
tions
may
central
204
203
202
184
183
182
181
180
Mean
SD
2.06
1.71
1.83
3.63
2.57
2.29
1.65
2.65
the
venous-arterial
transfer
the
counter-current
flow
...
2.36
testosterone
...
1.70
testosterone
2.03
±0.46
6.46
±2.33
2.31
±0.89
.
.
.
.
.
.
2.58
1.47
reequilibration
Since
2.16
±0.48
of
predict.
This
is
greater
than
EA
(n
=
8;
P<
EA
is
not
significantly
is not significantly different from
different
from
where
ischemic
this
either EA.
2
and
situ
the
slowing
bound
down
and
to
unbound
available
more
free
distort
are
plexus
testicular
artery
However,
from
so
not
that
the
to
in
the
preparablood
the
is
testis
spermatic
endogenous
meaningful.
the
difficult
a problem
pampiniform
separated
the
directions,
present
analysis.
are
would
opposite
not
the
preparation,
measurements
from
sufficiently
artifacts
does
all
for
j.zl
condi-
enhance
by
rate
factors
in
sampling
in
tion,
available
Corpus
Caput EA.
FA
significantly
flow
directly
making
picture
effects
rat
transfer.
these
transfer
of
the
5
static
of
thus
estimates
1977),
alternatively,
5.55
5.34
5.12
4.98
8.29
9.79
9.26
3.34
for
on
blood
or,
2.98
1.84
1.65
2.28
2.06
1.98
1.94
1.47
permit
artery
passing
approximately
pull
system
ex-
from
Free,
under
merely
stop-
testicular
the
contains
samples
arterial
perfused
TA
0.005).
(see
artery
blood.
Caput
EA
of
for
Catheters
blood
Based
length
artery
venous-arterial
of
obstacle.
and
in
plasma
difficult,
spasms
the
11-13%.
concomitant
the
prevent
the
radius
Rat
no.
without
effectively
only
testicular
is technically
needles
In
increase
sufficient
through
system
which
the
obtain
assay
of
change
TABLE
change
artery.
fusate.
to
blood
5-fold
levels.
to
from
animals
rabbit,
to
local
amounted
sampling
small
2-
blood
the
in
and
arterial
a
arterial
levels
However,
circuit
rat
in
monkey,
the
the
increase
the
showed
central
in
through
testosterone
rhesus
popula-
showed
local
in
at
for
analysis
levels
This
testis
over
and
sample
passed
highest
of
the
ram
blood
short
levels
increase
higher
pampiniform
the
when
at
artery
(see
plexus.
was
entering
molecules
appear
pampiniform
in
monkey)
it
the
1977
statistical
testosterone
when
concentration
where
demonstrated
labeled
vein
general
review).
must
of
blood
as
and
Free,
which
rhesus
of
blood,
measured
(see
for
and
the
tes-
vein
been
in
elevation
in
artery
enough
be-
potential
Endogenous
spermatic
species
ram
significant
the
testosterone
species
large
exists
exists
have
Those
to
a concentration
testicular
the
circulation,
vein
normally
of
11 mammalian
was
from
since
there
in
in
and
testosterone,
circulation.
with
the
Free
1973;
pass
and
vessels,
levels
to
al.,
that
tract
tosterone
tracer
steroid,
concentration
compared
therefore,
material
testosterone
2
local
from
the
et
fashion
for
the
least
vein
cannot,
recently
types
testicular
concentrations
this
disconnected
(Free
substances
reproductive
appears
to
and
have
5
least
the
641
with
dextran
in
for
femoral
spermatic
distal
arteries
studies
at
1975).
the
testicular
tween
DISCUSSION
that
Jaffe,
As
gradient
experiments,
plexus
by
perfused
general
from
epididymis
or
the
S.D.).
of these
were
blood
and
S.D.)
in the
artery
and
artery
assayed
PLEXUS
testis
among
of testosterone
that
pampiniform
epididymal
were
PAMINFORM
testicular
and
from
artery
(1.73
from
transferred
artery
blood
level
conditions
testosterone
testos-
systemic
9 rats
of
mean
artery
significantly
(1.95 ± 1.14
that
arterial
epididymal
differ
artery
the
of
the
The
epididymal
to
if endogenous
samples
of
mean
testicular
between
branch
is
a
higher.
determine
arteries,
superior
yield
similar
3-fold
IN THE
8 experiments
while
than
differed
epididymal
not
The
radioactivity
femoral
were
In
in
of
1.
artery
the
levels
A summary
Table
epididymal
TRANSFERRED
is
vein
hormone
Even
though
642
FREE
these
considerations
values
for
endogenous
earlier
studies
Tillson,
1975)
facts,
the
of the
lead
(Free
(such
pling
as
ports
strated
that
5
for
sampling
the
ranged
testicular
from
with
that
testicular
with
demon-
by
can
from
the
femoral
a result
assay
is intact.
of
similar
endogenous
testo-
sterone.
Since
the
derive
caput
their
testicular
and
arterial
artery,
ferred
the
androgens
one
or
the
of
the
Einer-Jensen
(1974)
obtained
in
the
ipsilateral,
testosterone-3
H
into
the
ducts
contralateral,
efferent
were
occluded.
we
have
cules
found
pass
terial
no
into
the
to
is
tions
showing
the
that
proximal
to
artery
result,
the
the
major
via
Einer-Jensen
The
of
tuon
(Free
arise
apposition
In
connections
view
to
the
of
this
between
to be a more
reported
by
mechanism
and
has
does
testosterone
not
to
tissues.
in
the
has
been
shown
to be a
exchange
that
is conwithin
the
physiological
spermatic
mechanism
didymal
This
observa-
(1976).
range
it
thus,
arteries
appears
the results
molecular-exchange
pampiniform
plexus
passive
counter-current
centration-limited
rats,
and
supply.
anatomical
1927).
venous
mole-
venous-ar-
artery
blood
venous
the testis
and epididymis
likely
explanation
for
study
these
epididymal
(Andres,
a route
present
via
testicular
with
of
when
lymphatics
the
that
arterial
consistent
testicular
in
epididymis
epididymal
result
even
vein
testosterone
Jaffe,
1975).
physiological
appear
the
to
If
concentra-
iniform
supply
Soc.
Exp.
223,
J.
and
plexus
241-248.
Jaffe,
R.
A.
testosterone
of
the
(1975).
transfer
rat.
Dynamics
in the
Endocrinology
of
pamp97,
M. J. and Tillson,
S. A. (1976).
Local
increases
in concentration
of steroids
by
venous-arterial
transfer
in the pampiniform
plexus.
In: Hormonal
Regulation
of Spermatogenesis.
(F. S. French,
V.
Hansson,
E. M. Ritzen
and
S. N. Nayfeh,
eds.),
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pp. 181-194.
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R. A., Jam,
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W. R.
(1973).
Testosterone
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in
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reproductive
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of the
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Free,
M. J. (1977).
Blood
supply
to the testis
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role
in local
exchange
and transport
of hormones
in the male
reproductive
tract.
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(A.
D. Johnson
and
W. R. Comes,
eds.).
Vol.
IV,
Academic
Press,
New York.
pp. 39-89.
Ginther,
0.
J., Mapletoft,
R. J., Zimmermann,
N.,
Mecldey,
P. E. and Nuti,
L. (1974).
Local
increase
in
testosterone
concentration
in the
testicular
artery
in rams.
J. An. Sci. 38, 83 5-837.
Jacks,
F. and
Setchell,
B. P. (1973).
A technique
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studying
the transfer
of substances
from
venous
to
arterial
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in the spermatic
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17P.
Jaffe,
R. A. and
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M. J. (1972).
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flowmeter
for use in rat testicular
artery
and
other
small
vessels.
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571-573.
R.
A. and
Free,
M. J. (1973).
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anesthesia
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Sci. 23, 266-269.
Resko,
J. A., Malley,
A., Begley,
D. and Hess,
D. L.
(1973).
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of testosterone
during
fetal
development
of the
rhesus
monkey.
Endocrinology
93,
156-161.
Jaffe,
this exchange
significance,
in
involve
androgen-dependent
Proc.
Free,
with
injection
mechanism.
169-177.
specific
after
associated
indication
the
transfer
to
and
via
testis,
M.
venous-arterial
artery.
compared
However,
Free,
trans-
epididymis
a higher
rat
Physiol.
the
for
epididymal
epididymis
the
from
exists
enter
branches
radioactivity
the
epididymides
supply
potential
to
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Biol. Med.
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236-242.
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Local
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l HI testosterone
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the testis
to the
epididymal
fat pad and the corpus
epididymidis
in
the rat. J. Reprod.
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M. J. and Jaffe,
R. A.
(1972).
Dynamics
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in the testis
of the conscious
rat. Am. J.
artery
quite
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Evidence
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one
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enter
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supply
blood
4.3
of
sam-
1972])
blood
-
a mean
obtained
nonoc-
the
shunts
artery
2.1
be indicative
testosterone
testicular
and
arti-
Unpublished
Free,
directly
of
in
Free
using
AL.
the
sampling
yet
loop
and
artery
rats,
levels
to
laboratory
radiolabeled
when
In
our
Jaffe
that
1972;
to
may
plastic
[see
testicular
vein
al.,
situation.
techniques
artery
the
et
obtained
from
believe
blood
levels
rats published
subject
physiological
experiments
to
artery
in
were
values
true
elusive
us
testicular
testosterone
ET
of
epi-