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Experimental cryptorchidism in adult male ratsHistological and hormonal sequelae.

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Experimental Cryptorchidism in Adult Male Rats:
Histological and Hormonal Sequelae
THOMAS M. JONES, WINSTON ANDERSON,' VICTOR S. FANG,
RICHARD L. LANDAU AND ROBERT L. ROSENFIELD
The University of Chicago Pritzker School of Medicine, The Biomedical Center for Population
Research, Chicago, Illinois 60637 U S A .
ABSTRACT
Mature male rats were rendered cryptorchid and followed for up
to nine weeks during which serial blood specimens were obtained for multiple
hormonal analyses; serial testicular samples were obtained as well. In contrast
with control animals, cryptorchid rats showed transient rises in FSH which returned to normal a t the end of the study; estrogen levels were high in the final
weeks. Plasma testosterone levels were unchanged and LH levels changed little.
Light and electron microscopic studies of testicular biopsy specimens showed
prompt disruption of spermatogenesis which became more extensive with time.
Sertoli cells underwent multiple changes including increased lipid storage and
phagocytosis of spermatozoa. Comparisons are made between the sequence of
hormonal changes and that of histological changes. In addition, questions are
raised concerning the ways in which Sertoli cells are affected by experimental
crypt orchidism.
In many mammalian species, including
man, cryptorchidism is associated with either
greatly reduced or absent spermatogenesis
(Albescu et al., '71;Atkinson, '73a,b; Carver,
'58; Charney, '60; Cummins and Glover, '70;
Davis and Firlit, '66; de la Balze et al., '60;
Farrington, '69a,b; Fechheimer, '70; Giarola,
'70; Hecker and Heinz, '67; Robinson and
Engle, '54; Scott, '62). Because histological
damage to the germinal epithelium seems to
far outstrip the damage done to interstitial
tissue in both naturally occurring and experimental cryptorchidism (Altwein and Gittes,
'72; Leeson and Leeson, '70; Liptrap and
Raeside, '70;Mancini et al., '65; Sohval, '54),
the artificially cryptorchid mammal has been
used as a tool to explore possible hormonal
feedback relationships between the anterior
pituitary and the germinal epithelium. Previous studies of artificial cryptorchidism in
rats have tended to concentrate either on histological observations (Chowdhury and Steinberger, '72;Davis and Firlit, '66; Jansen, '70;
Lee and Fritz; '72; Leeson and Leeson, '70;
Parvinen, '73;Saba et al., '72) or on hormonal
observations (Altwein and Gittes, '72;Amatayakul et al., '71;Inano et al., '68; Lloyd, '72;
Morehead and Morgan, '67a,b; Steinberger
ANAT. REC., 189: 1-28
and Duckett, '66; Stockton and Johnson, '68;
Swerdloff et al., '71; Walsh et al., '70). We
report here a study of experimental cryptorchidism in rats which compares serial observations of the changes induced in testicular
histology and simultaneous serial measurements of plasma levels of luteinizing hormone, follicle stimulating hormone, testosterone and estrogen.
METHODS AND MATERIALS
Sixty-day old male Sprague-Dawley rats
were allotted to several major treatment
groups. In the control group (N = 30)a sham
operation was performed. In the sham operation, r a t s were ether anesthetized, each
scrotal compartment was entered, and the
testes were manually moved into the abdominal cavity. The incisions were closed and the
testes were then massaged back into the
scrotal compartments. In the castrate group,
(N = 30)both testes were removed through a
single abdominal incision. In the cryptorchid
group (N = 30) both scrotal compartments
were entered, the testes placed into the abdoReceived Sept. 8, '75. Accepted Jan. 4, "77.
'Present address: Department of Zoology, Howard University,
Washington, D.C. 20059.
1
2
JONES, ANDERSON, FANG, LANDAU AND ROSENFIELD
men and the iguinal canal sealed so that the
testes could not re-enter the scrotum.
Five rats from each group were then bled by
cardiac puncture a t various time intervals
ranging from 24 hours to 9 weeks.
In addition, a small group of cryptorchid
rats (N = 5) was castrated six weeks after the
initial operation and bled three weeks after
this castration. Rats from both the cryptorchid and the sham operated groups were sacrificed a t intervals ranging from 24 hours to 9
weeks. Testes were excised from ether anesthetized animals and fixed by perfusion for
ten minutes with 2% glutaraldehyde in 0.2
molar-S-collidine buffer (pH 7.2) a t room temperature. Subsequently the testes were cut
into slices and immersed for an additional 45
minutes in cold (4°C) glutaraldehyde-collidine fixative of the same molarity and pH. The
testis slices were then immersed for one hour
in 1% OsO,, rinsed in collidine buffer, dehydrated in alcohol water solutions and emhedded in Epon. Semithin sections (1-2 pm) were
stained with Toluidine Blue solutions for
light microscopic examination. Thin sections,
stained with uranyl acetate and lead citrate,
were examined with a Siemens 101 electron
microscope.
Serum levels of testosterone were measured
by radioimmunoassay after preliminary isolation of testosterone by thin-layer chromatography (Chen et al., ’71). Serum estrogen was
measured by radioimmunoassay technique as
described by Wu et al. (‘731, using a specific
antiserum provided by Doctor G. E. Abraham,
Harbor General Hospital, Torrance, California. Serum levels of luteinizing hormone (LH)
and follicle-stimulating hormone (FSH) were
determined by radioimmunoassay techniques
using the purified hormones and specific antisera provided by National Institute of Arthritis, Metabolism and Digestive Diseases, NIH
(Monroe et al., ‘68; Parlow et al., ’69).
RESULTS
Morphological aspects
The germinal epithelium in seminiferous
tubules of 24-hour sham operated rats appeared normal with respect to spermatogenesis (fig. 1).Within 24 hours of transfer of the
testes to the abdominal cavity, effects of the
altered milieu could be seen. Light microscopic examination showed a “balling-up’’ of the
spermatids and spermatocytes (figs. 2,3). The
formation of multinucleated spermatids (figs.
4, 7, 8) was associated with the enlargement
of intercellular cytoplasmic bridges (fig. 6)
which are‘ normally narrow and contain few
organelles. With the widening of the cytoplasmic bridges,the cytoplasm of spermatids became admixed (figs. 7, 8) and nuclei were
sometimes juxtaposed and attached by acrosoma1 vesicles. These cytoplasmic changes
were correlated with the disorganization of
the manchette microtubular system in spermatids (fig. 4), distortion of the nucleus and
the disorganization of chromatin (figs. 4, 5,8).
Spennatids of all stages of development
underwent degeneration and all cellular
events leading to maturation of sperm seemed
to stop.
Five days after the operation, multinucleated spermatids and sloughed cells were a
prominent feature in all tubules (fig. 10). Late
spermatids were frequently found a t the base
of Sertoli cells. Nuclei, chromatin, connecting
pieces and middle pieces of spermatids were
observed within membrane-bounded vacuoles
in varying stages of degeneration (figs. 11,
12). Sertoli cells possessed well-developed
cisternae of the granular and agranular endoplasmic reticulum and Golgi apparatus. An
increase in lipid droplets and microtubules
within Sertoli cells was also evident.
In the 21-day cryptorchid testes (fig. 14)
three types of seminiferous tubules were seen.
The type A tubules had a dilated lumen surrounded by highly branched Sertoli cells that
stored little lipid. Close examination revealed
the presence of a few spermatogonia in pockets beneath the Sertoli cells. In type B
tubules, the germ cells were seen to be in
different states of maturation up to secondary
spermatocytes. The germ cells were sloughed
as spermatids were seen in these tubules. Sertoli cells in type B tubules accumulated a considerable amount of lipid. The type C seminiferous tubules possessed Sertoli cells that
crowded into the lumen and stored more lipid
than was seen in the type A tubules. Spermatids were not present within type C
tubules. Spermatogonia were seen in all cross
sections and the impression was gained that
these primordial cells could differentiate up
to, but not beyond, the spermatocyte stage.
Thirty-six days after the operation the
seminiferous tubules showed signs of continued degeneration (figs. 15, 16). Huge stores
of lipid were seen within the Sertoli cells and
in those germ cells which had matured to the
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
spermatocyte stage. Type B tubules were now
most numerous.
By 64 days, all seminiferous tubules were
reduced in diameter and possessed neither
spermatocytes nor spermatids (fig.17). Sertoli
cell processes occluded the lumen, and lipid
storage was much reduced within their cytoplasm (fig. 18). The seminiferous tubule wall
was thickened, partly as a result of the accumulation of basement lamina-type matrix at
the base of the Sertoli cells and between the
myoid cells. At this stage, myoid cells had
dilated cisternae of the granular endoplasmic
reticulum and of the Golgi apparatus. A number of seminiferous tubules were completely
occluded by mineralized electron-dense material. Other seminiferous tubules contained intact and apparently normal spermatogonia
(fig. 19). The junctions between the Sertoli
cells surrounding spermatogonia appeared to
be intact. Because of the marked reduction in
the size of the seminiferous tubules, the peritubular lymphatic spaces appeared larger.
They were bounded by cords of interstitial tissue and blood vessels (fig. 19).
In comparison with the profound changes in
germinal epithelium induced by cryptorchidism, the sham operation had no effect (figs. 1,
9, 13). Furthermore, cryptorchidism had no
morphological effect on interstitial cells a t
any stage, and even when destruction of germinal epithelium was most advanced, interstitial cells were rich in agranular endoplasmic reticulum (fig. 201, suggesting active
steroidogenesis. This suggestion is confirmed
by the hormonal data reported below.
3
24). Castration induced prompt and sustained
rises in both LH and FSH whether it was performed initially or following cryptorchidism
(figs. 23, 24).
DISCUSSION
It is clear that inducing bilateral cryptorchidism in several species of laboratory mammals, as well as in the rat, leads to a prompt
disorganization of germinal epithelium (Cummins and Glover, '70; Ploen, '72) the reversibility of which has been shown to be dependent upon the length of time allowed to lapse
before repositioning of testes back in the
scrotum (Atkinson, '73a,b; Hagen, '71).
In the present studies, the extent of germinal epithelium disruption is time dependent. The longer the testis remains in the abdomen, the more curtailed is spermatogenesis.
A similar temporal factor is noted in a study
by Chowdhury and Steinberger ('72) which reported that the cryptorchid milieu could support some degree of spermatogenesis in the
rat, but with time, spermatogenesis ceased.
At no point in our study did we note the reappearance of normal spermatogenesis such as
had been reported by Saba et al. ('72) 60 days
after artificial cryptorchidism in mature rats.
An extensive literature (see Vandemark
and Free, '70, for a review) has attempted to
document not only the effects of elevated temperature on germinal epithelium histology
but also the inference that the effects of
cryptorchidism are chiefly those of an admittedly subtle elevation of testicular temperature (Parvinen, '73; Ploen, '72). The activities
of certain enzymes correlated with spermatoHormonal aspects
genesis have been shown to be altered by
In keeping with the histological appearance cryptorchidism (Vanha-Pertulla, '73) and inof normal interstitial cells, plasma testoster- direct evidence has been reported showing the
one levels in cryptorchid rats did not differ release of enzymes by thermally sensitive
from controls (fig. 21). It should be noted that lysosomes in the testis following artificial
the wide variation in plasma testosterone in cryptorchidism (Lee and Fritz, '72).
both intact and cryptorchid rats is apparently
The use of electron microscopy as well as of
typical of rats and mice (Bartke et al., '73). light microscopy has enabled us to highlight
Testosterone concentrations dropped quickly some early alterations in spermatogenesis infollowing castration.
duced by artificial cryptorchidism. Within 48
Plasma estrogen levels tended to drop in all hours after cryptorchidism, alterations seen
groups with increasing age (fig. 22). However, in electron micrographs are clearly signs that
plasma estrogens in cryptorchid rats were spermatogenesis is disrupted. Spermatocytes
higher than controls in the final study periods. and spermatids of all stages are affected. The
Plasma LH levels (fig. 23) were little affected disruption of the manchette microtubular system in spermatids is probably due to depolyby cryptorchidism.
In contrast, plaama FSH levels were tran- merization of the microtubular subunits.
siently elevated following cryptorchidism (fig. Whether such depolymerization is induced by
4
JONES, ANDERSON, FANG, LANDAU AND ROSENFIELD
an increase in temperature or by some other
factor of artificial cryptorchidism is not clear.
Other major alterations in spermatid cytoplasm include fragmentation of acrosomal
vesicles and the agglomeration of adjacent
spermatids as the cytoplasmic bridges within
each clone widen. Binucleate and multinucleated spermatocytes and spermatids were
sloughed into the lumen.
Throughout normal spermatogenesis, the
Sertoli cells bear an intimate but incompletely understood relationship to maturing germ
cells. They resumably maintain the blood
testis barrier and may function in a supporting and perhaps secretory role (Vitale et al.,
'73). In the cryptorchid rat testis, the structure and function of the Sertoli cells alters
considerably. By five days, not only have the
later stages of spermatogenesis become disrupted but phagocytosis of late spermatids by
Sertoli cells has increased considerably. By 36
hours huge lipid stores were apparent in Sertoli cells. The loss of the spermatocytes and
spermatids from the epithelium resulted in
the formation of smaller tubules the lumens
of which were occluded by Sertoli cell processes.
In the present study, interstititial cell morphology was not significantly distorted up to
nine weeks after cryptorchidism. Androgen
production, presumably by interstitial cells,
was not altered. Several mammalian species
have been shown to have either lower androgen production or lower androgen reserves following cryptorchidism (Engberg, '49; EikNes, '66; Liptrap and Raeside, '71, '72). In
rats, however, results have been contradictory
(Amatayakul et al., '71; Inano and Tamoki,
'60; Lloyd, '72; Morehead and Morgan, '67a).
We did not perform studies seeking to evaluate Leydig cell reserve, but our results suggest that no differences in plasma testosterone are apparent up to seven weeks. Whether
plasma testosterone levels are maintained in
the cryptorchid rats by increased LH release
by the pituitary, in the manner of a partial
end organ failure, is a subject for speculation;
the idea receives limited support from our gonadotropin data.
We are unaware of previous studies of
estrogen production in cryptorchid rats. In
the present study, estrogen production was altered in the final period. Whether the elevated
estrogen seen in 9-week cryptorchid rats is a
result of altered steroid conversion and/or
production by the Leydig cell is not clear. A
fascinating possibility is that estrogen is produced by a more metabolically active and altered Sertoli cell.
Several. studies have followed either directly or indirectly changes in anterior pituitary gonadotropin production following the
induction of cryptorchidism in rats. Because
it is apparent that cryptorchidism has different effects on gonadotropin levels depending
upon the sexual maturation of the rat a t the
time of operation (Morehead and Morgan,
'67b; Walsh et al., '701, we shall discuss only
studies of sexually mature rats.
Morehead and Morgan ('67b) noted an
increase in the number of signet-ring gonadotrophs which appeared in the anterior pituitary following cryptorchidism, and the anterior pituitary was heavier in mature cryptorchid rats than in controls. Steinberger and
Duckett ('66) found that both the LH and
FSH content in pituitaries rose following
cryptorchidism, however, no comparison with
normal rats was made. Walsh et al. ('70)
reported that artificial cryptorchidism in 49day rats induced rises in both LH and FSH
within four days. The authors note that those
elevations were never as dramatic as those
induced by castration. Amatayakul et al. ('71)
also reported significant elevations of FSH
and LH following cryptorchidism in mature
rats 14 to 59 days after operation. Again,
these were not as high as those induced by
castration. Finally, Altwein and Gittes ('72)
using 63-day rats found rather prompt and
persistent elevations of plasma FSH but
marginal LH elevations only apparent a t the
end of the nine week period after cryptorchidism.
Our results are more similar to those of Altwein and Gittes. We observed no significant
changes in LH and testosterone. The rise and
fall pattern we obtained in serum FSH levels
has not been previously reported. If in fact we
had found a return of spermatogenesis such as
that reported by Saba et al. ('72) we would
have a convenient explanation for this pattern based on notions of a n hitherto much
speculated upon but not yet delineated feedback loop between the germinal epithelium
and the hypophysis. However, a t 63 days when
cryptorchid FSH levels are not different from
controls, there is no return of spermatogenesis
seen.
Although the cryptorchid mammal has
been used as a model to explore various
aspects of hypophysial-testicular relation-
5
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
ships, it can be seen from the present study
that the effects of cryptorchidism on the
testes are so complex that answers are not
easily obtained. If, in fact, testosterone levels
and LH production are intimately bound in a
classic feedback loop in male rats, then the
lack of alteration in both LH and testosterone
is predictable. The major problem, as far as
classical endocrinological theory is concerned,
is to explain a transient rise in FSH levels. Although significant impairment in spermatogenesis is seen within 48 hours, FSH elevations were not seen until seven days had
elapsed, a t a time when Sertoli cells were morphologically altered. The enzymatic machinery for steroid synthesis exists in Sertoli cells
(Lacy and Petit, ’70)and it may be that Sertoli cells normally secrete a product which informs the hypothalamo-hypophysial system
about spermatogenesis. Altered Sertoli cell
morphology may reflect impaired output of
this hypothesized product, which in turn
would be followed by a n increase in FSH
levels. Increased plasma estrogen levels could
be a result of increased FSH stimulation of
interstitial cells, or, as suggested earlier, of
active synthesis by Sertoli cells. The return of
FSH levels to those of control animals could
be brought about by high plasma estrogens.
Alternately, the hypertrophied Sertoli cells
seen in the 64-day cryptorchid rat could be
synthesizing sufficient amounts of the hypothesized “feedback product” to return FSH
levels to control. Whatever the answer is, it is
clear that simple feedback control mechanisms fall short of explaining the relationship
between germinal epithelium morphology and
gonadotropin production so far as cryptorchidism is concerned.
ACKNOWLEDGMENTS
Doctor Jones wishes to acknowledge the
support of the Gerald Sokolec Foundation.
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I
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PLATES
PLATE 1
EXPLANATION OF FIGURES
1 Cross section of seminiferous tubule from a sham operated rat 24 hours after operation. The germinal and Sertoli cells are undisturbed within the tubule. spzoa, spermatozoa. X 150.
2,3
8
Cross section of seminiferous tubule from a cryptorchid rat 24 hours after operation. Binucleate and multinucleated spermatids appear as large rounded structures
within the epithelium. At higher magnification, clear regions in the nuclei of spermatids (asterisk: fig. 3) represent areas of disorganized chromatin. Figure 2 X 150;
figure 3 X 400.
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
Jones, Anderson, Fang, Landau and Rosenfield
PLATE 1
9
PLATE 2
EXPLANATION OF FIGURES
4 , 5 Electron micrographs of spermatids from the cryptorchid rat 24 hours after the
operation show highly distorted nuclei with uncondensed chromatin regions. The
insert (fig. 4)shows a multinucleated spermatid. Arrows (fig. 4) indicate remnants
of the manchette microtubular system. The acrosomal cap becomes vesiculated
(dark triangles: fig. 5). M, mitochondria; n, nucleus; NR, nuclear ring. SC, Sertoli
cell. X 360; insert X 9,000.
10
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
Jones, Anderson, Fang, Landau and Rosenfield
PLATE 2
PLATE 3
EXPLANATION OF FIGURES
6 , 7 Spermatids from the 24-hour cryptorchid r a t testis are illustrated in these micrographs. The enlarged intercellular bridge is shown in figure 6. In figure 7, the cytoplasm of two spermatids is mixed ahd nuclei lie adjacent to each other. Acrosomal
vesicles (Av) are also illustrated. X 7,200.
12
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
PLATE 3
Jones, Anderson, Fang, Landau and Rosenfield
13
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
Jones, Anderson, Fang, Landau and Rosenfield
EXPLANATION OF FIGURES
8 The cytoplasm of a multinucleated spermatid of a 24-hour cryptorchid rat testis.
Portions of several nuclei (N)are illustrated. The acmsomes are vesiculated and
invaginated, and mitochondria are randomly distributed in the cytoplasm of these
cells. X 6.300.
9, 10 Transverse sections through seminiferous tubules of a sham operated rat five days
after the operation (fig. 9) and of a cryptorchid rat five days after the operation
(fig.10).Germinal and Sertoli cells are undisturbed in the sham-operated tissue.
Sloughed spermatid syncitia are present in the tubular lumen of the cryptorchid
testes (fig.10). X 150.
14
PLATE 4
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
Jones, Anderson, Fang, Landau and Rosenfield
PLATE 5
PLATE 6
EXPLANATION OF FIGURES
11, 12 The basal regions of Sertoli cells of the 5-day cryptorchid rat testis are illustrated
in these micrographs. Membrane-boundedvacuoles contain resorbed spermatid
heads and middle pieces (MP); in various stages of degeneration. Profiles of the
granular endoplasmic reticulum (RER)and Golgi apparatus (GA)in Sertoli cells
are shown. A, acrosome; MM, mitochondria;N, nucleus. X 6,500.
16
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
Jones, Anderson, Fang, Landau and Rosenfield
PLATE 6
17
PLATE 7
EXPLANATION OF FIGURES
13.14 Transverse sections of tubules from a 21-daysham operated (fig.13)and 21-day
cryptorchid testis (fig.14).The sham operated tissue is undisturbed. Tubules in
the cryptorchid testis at 21 days are of three types: type A, with low Sertoli cells
and few spermatogonia (arrows);type B with Sertoli cells rich in lipid deposits
and with sloughed germ cells; and type C, with Sertoli cells (SC) rich in lipid and
few germ cells present. Is, institial cells. X 150.
18
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
Jones, Anderson, Fang, Landau and Roaenfield
PLATE 7
PLATE
8
EXPLANATION OF FIGURES
15,16 Seminiferous tubules from cryptorehid rat 36 days after operation. SertoIi cells
(S) in all tubules possess huge lipid deposits (1). Spermatocytes (sc), are being
sloughed into the tubule lumen, while spermatogonia (sg) are seen next to the
tubule wall. Figure 15 X 60; figure 16 X 300.
20
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
Jones, Anderson, Fang, Landau and Rosenfield
PLATE 8
21
PLATE 9
EXPLANATION OF FIGURES
17,18 Seminiferous tubules (ST) from a 64-day cryptorchid rat are illustrated in these
light micrographs. All tubule lumina are occluded by processes of Sertoli cells.
The lymphatic space surrounding the tubules is enlarged. The tubule wall (BL)is
thickened. IT, interstitial tissue. Figure 17 X 72; figure 18 X 270.
22
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
Jones, Anderson, Fang, Landau and Rosenfield
PLATE 9
23
PLATE 10
EXPLANATION OF FIGURES
19 Spermatogonium between Sertoli cells from the seminiferous tubule of a 64-day
cryptorchid testis. The apparentlynormal spermatogonium lies on a thickened basement lamina (BL). X 5,760.
20 Portions of the cytoplasm from interstitial cells from a 64-day cryptorchid testis.
These cells contain numerous tubules and cisternae of the agranular endoplasmic
reticulum (SER) and numerous mitochondria. X 5,400.
24
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
Jones, Anderson, Fang, Landau and Rosenfield
PLATE 10
25
PLATE 11
EXPLANATION OF FIGURES
21 Mean plasma testosterone levels following cryptorchidism and castration. Standard
deviations indicated on this and following figures.
22 Mean plasma estrogen levels following cryptorchidism and castration.
23 Mean plasma LH levels following cryptorchidism and castration.
24 Mean plasma FSH levels following cryptorchidism and castration.
26
SEQUELAE OF EXPERIMENTAL CRYPTORCHIDISM IN RATS
Jones, Anderson, Fang, Landau and Rosenfield
-
-+-CASTRATES
--o--
450 -
PLATE 11
1'
CRYPTORCHID
CONTROL
ESTROGEN
400 -
I
--.--CASTRATES
--o-- CRYPTORCHID
-CONTROL
--P CRYPTORCHID-
CASTRATES
90
8070
T
T
~
6050 -
4030 20 -
W
WEEKS
LH
nglml
CASTRATES
--o--
CRYPTORCHID
bCRYPTORCHID
-
,,
CASTRATES
,'
,,'
@O'
I
WEEKS
i
4
5
6
+
Q
9
1
2
WEEKS
3
4
5
6
7
8
9
'
'
'
'
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'
27
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