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Presence of the pituitary in perfect cyclopia.

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PRESENCE OF T H E PITUITaRY I N
PERFECT CYCLOPIA
K. T. ROGERS
Department of Zoology, Oberlin College, and The
Narine Biological Laboratory, Woods Hole
FOUR FIGURES
The absence of the oral hypophysis has been cited as being
characteristic in cyclopia. For example, Adelmann ( ’34, p.
264) states in relation to cyclopean Amblystoma embryos,
“The persistence of a median mesodermal continuity ventral
to the hypothalamus is correlated with the absence of the
anterior lobe of the hypophysis.” A detailed report on chick
embryos determined to cyclopia by operative procedures
(Rogers, ’51, abstract) will indicate the presence of both
pituitary components in most cases. A report is made here
on the presence of both the oral and neural lobes of the
pituitary gland in some experimentally produced fish hatchlings. An extensive search of the literature supports the data
from the present material, which indicates that the two portions of the pituitary may be either present or absent in
cyclopia, including cyclopia perfecta.
EXPERIMENTAL MATERIAL
Ten Pundulus heteroclitus perfect cyclopeans that had been
treated with solutions of magnesium chloride (Rogers, ’56)
were studied. Of the ten, three had hatched and were able
to swim. Before &cation all were allowed to use up most
of their yolk. Those that had not hatched were removed from
their chorions. The fish were fixed in Allen’s P F A modifioa‘This work was supported by a Public Health Service Grant, No. B-760, and
by aid from the Committee on Productive Work, Oberlin College.
213
214
K. T. ROGERS
tion of Bouin's fluid, cleared in amyl acetate, cut at 10 p, and
stained with the modification of the Bodian protargol stain
previously described (Rogers, '52).
Of the 10 animals, the three that hatched normally all
possess a pituitary gland, as does one that failed to hatch.
The other 6 fish lack any recognizable pituitary tissue. The
pituitaries that did develop are similar to controls in form,
position, and tissue components (figs. 3 and 4). The sections
of one normal control and the 4 cyclopeans that possess
pituitaries were projected from a carbon arc machine and
tracings made of the pituitary sections at a magnification of
1,750 times. These were cut out of the paper on which they
were traced and weighed on an analytical balance. With
the thickness of the paper causing weight to vary by about 4%
in a separate test, the weights of the pituitaries of the cyclopean animals were 44%,50%, 60%, and 82% of the weight
of the pituitary of the selected control animal raised the same
length of time in sea water.
I n a chart that tabulates position of nasal pits, bilaterality
of the telencephalon, presence or absence of a slight dorsal
notch in the pigment layer of the eye, presence or absence
of a ventral notch in the position of the former choroid fissure,
exact shape of lens, presence of eye muscles, and the aspect
from which the optic nerve leaves the cyclopean eye, only the
last named characteristic uniformly differed between the
group with pituitaries and the group lacking them. I n the
animals that possess pituitaries the eye is directed more
anteriorly and the optic nerve leaves the eye posteriorly (fig.
2). I n the animals that lack pituitaries the eye is directed
more ventrally and the nerve leaves the eye dorsally, immediately entering the brain (fig. l), which means that the
eye in these cases is situated farther posteriorly beneath the
brain.
DISCUSSION
The median massing of the substrate (Adelmann, '34),
which frequently results in selective fusion (or failure of
PITUITARY I N PERFECT CYCLOPIA
215
division) of the various eye muscle components in cyclopia,
would seem not to be the immediate factor in the presence
or absence of the pituitary in the present cases. Eye muscles
were massed medially and related to these cyclopean eyes
in essentially the same positions in every case. When the eye
developed in such a position that its posterior extent and the
eye muscles upon its surface impinged on the normal pituitary
area, the pituitary was absent. When the eye developed
farther forward beneath the brain and its nerve reached the
brain by leaving the eye posteriorly, the normal pituitary
region was free of eye and eye-muscle tissue, and in every case
pituitary tissue developed, although not in amount equal to
that of the control.
It seems worthwhile to summarize and make available in one
place all the cases found in the literature that specifically
mention the presence or absence of the pituitary in cyclopia.
Dr. H. Edmonds ('50) mentions that in reviewing 63 references located primarily through the Index Catalogue Fourth
Series, the presence or absence of the pituitary was specified
only 11 times, and he has kindly furnished several references
that had not previously been included in the present listing.
Thanks are also due Prof. P. Pasquini, Prof. F. 0. Llorca, and
Prof. G. W. Bartelmez for furnishing unpublished information,
and to Dr. G. Abrams for sccuring certain references. The
appendix shows that the oral hypophysis is present in over
half the cases, and that the ratio rises if experimental cases
are excluded. Prof. Bartelmez's identification of oral hypophysis in the 6.5 mm human embryo originally described
by Mall ( '17), indicates that the pituitary probably could be
located in additional cases if one could look specifically for it.
This might or might not counterbalance the probable tendency
of workers to omit mention of the pituitary in its absence.
The important fact is that the oral hypophysis is often present
in all grades of cyclopia, including cyclopia perfecta. The
present cases seem to be the first report of the presence of
the pituitary in perfect cyclopia determined experimentally.
Two cases in the literature report its presence in spon-
216
I(.
T. ROGERS
taneously occurring perfect cyclopia (fish and horse). I n
judging cyclopia, spontaneous cases should be considered the
norm.
SUMMARY
1. The presence of the pituitary is noted in 4 Fundulus
perfect cyclopeans determined to cyclopia by magnesium
chloride solutions. Its presence is correlated with the position
of the eye, which does not impinge on the normal area in
which the pituitary is found.
2. The absence of pituitary is noted in 6 perfect cyclopean
embryos from the same experimental series. Its absence is
correlated with the position of the eye, which causes the eye
and its muscles to impinge on the area normally occupied by
the pituitary.
3. Cases of presence or absence of pituitary components in
cyclopia that were found in the literature are summarized in
an appendix.
APPENDIX
Cases of cyclopia in which presence or absence of oral hypophysis is specified
Hypophysis presumed present
** Hypophysis identified by histological sections
*** Cyclopia perfecta, hypophysis identified by histological sections
Adelmann, H.
'34 Amblystoma. (Experimental, mainly
Lic1,). Anterior lobe of hypophysis absent (histological sections).
J.E.Z.,67
**Barber, A. and
R. Muelling
'50 Human. Poorly organized eye in single
orbit. Oral hypophysis present (histological sections, photomicrograph, chromophobe and eosinophil ceUa identified).
Arch. of
Ophth., 43
'06 Human. Synophthalmia. Pituitary present.
Russ. Vrach,
* Batuev, N.
** Bartelmez, G.
Black, D.
.
5
'54 Human (Streeter 's horizon xvi) Close
synophthalmia. Oral hypophysis present,
abnormal (histological sections).
Human (horizon xix) . Synophthalmia.
Small irregular mass of cells interpreted
as oral hypophysis. (Sections, poorly
preserved material).
Human (horizon xvii). Re-examination
of Mall's ('17) 6.5embryo. Close
synophthalmia. Oral hypophysis present
as slim epithelial cylinder, attached t o
oral epithelium (sections).
Personal
communication
'13 Human. Partly doubled eye. Fossa
thought to be hypophyseal recess.
J. Comp.
Neur., ,
%
'
3
217
PITUITARY I N PERFECT CYCLOPIA
'36 Human. Single eye. No nerve I or 11,
no pituitary or sella turcica.
Arch. of
Ophth., 15
De, M. and
H. Dutta
'39 Human. Stated single eye, but no in-
J. Anat.,7.9
** Edmonds, H.
'50 Human. Anterior pituitary present in
two cases, one closely synophthalmic,
other "single eye and single pupil";
absent in three other cases. (Histological
sections.)
Arch. of
Path.40
'06 Fish (trout). Spontaneously occurring.
One case of cyclopia perfecta with welldeveloped eye, hypophysis present. Two
cases of reduced single eye, hypophysis
absent. (Histological sections.)
Proc. Zool.
SOC.Lond.,
1906
'40 Horse. Two eyes in a single orbit. Pitu-
Vet. J.
Lond., 96
Der Brucke, M.
*** Gemmill, J.
* Hughes, H. and
J. Drmsfield
ternal description. No pituitary fossa.
itary normal.
** Humphrey, R.
'24 Human. Double corneal areas, but single
Klopstock, A.
'21 Human. Cornea bean-shaped. Pituitary
poorly preserved. Sella turcica narrow
but deep.
vitreous with no trace of a median
septum. Neural and buccal hypophysis
present (histological sections).
Anat. Rec.,
g8
Monatschr.
f. Geburt.
u. Gynaek.,
56
** Llorca, F.
'52 Human (horizon xxii). Close synophthalmia. Oral and neural lobes present,
reduced (histological sections).
IV supp.
Rev. Arch.
Espan.
Morf.
'54 Human 16.5 mm.
Hypophysis present
(sections). Eye with two atrophic lenses,
single retina and tapetum, no optic
nerve.
Personal
communication
and
W. Filatow
'26 Horse. Cyclopia perfecta, oral hypophysis present. (Histological sections, eosinophil, basophil, and chromophobe cells
identified). Neural lobe absent.
Arch. f.
Augenh., 97
* Marburg, 0.
'43 Human. Partly double anterior portion
J. Neuro-
*** Lyssenkow, N.
and
F. Mettler
Mettler, F. and
C. Mettler
* Niigeli, 0.
of eye. Hypophyseal attachment labelled
i n figure of brain.
path. and
Exp.
Neurol,. 2
'37 Human, the eye not fully described,
Anat. Rec.,
68
stated perfect cyclopia (emphasis on
brain). Notch filled with fibrous connective tissue interpreted as hypophyseal
fossa (optic nerve composed of same
sort of fibrous tissue).
'97 Human. Two corneas! posteriorly one
eye and nerve. Pituitary present in
well-developed sella turcica.
Ognew, B.
'30 Human. Partly double eye. Small pitu.
itary present in sella turcica.
ROUX'Arch.,
5
Anat. Anz.,
70
218
I(.
T. ROGERS
Ozawa, M.
'39 Human. Two corneas, posteriorly one
eye and nerve. Infundibulum present,
oral hypophysis absent.
Jap. J. M.
Sc. Path., 4
Pasquini, P.
'42 Axolotl. (Experimental, centrifugation.)
Neural and oral hypophysis absent (histological sections).
Arch. It.
Anat.
Emb., 47
Philsalix, C.
'89 Sheep. Cyclopia perfecta, infundibular
J. 1'Anat.
depression present, pituitary body absent.
Human. Partly double anterior portion
of eye, one optic nerve, pituitary body
present.
*
*** Rogers, K.
Physiol., 25
'51 Chick (experimental, operative procedures). Cyclopia perfeeta, oral and
neural lobes of pituitary present (histological sections). Pituitary not reported in the abstract.
Anat. Rec.,
111
Rothschild, P.
'25 Human. Two small eyes i n one orbit.
Hypophysis absent.
Beitr.Path.
Anat. allg.
Path., 73
Smith, 8. and
B. Boulgakow
'26 Human. Partly double eye, one nerve.
No pituitary fossa
J. Anat., 61
Torrey, T. and
W. Breneman
'40 Frog (Experimental, centrifugation).
Pituitary absent (histological sections).
Proc. Ind.
Ac. Sc., 60
'09 Human. Two separate orbits and eyes
(called ''incipient cyclopia '' by the
author). Small pituitary fossa present.
J.Anat.
Physiol., 44
* Watkyn-
Thomas, F.
LITERATURE CITED
ADELMANN,
H. B. 1934 A study of cyclopia in Amblystoma punctatum, with
special reference to the mesoderm. J. Exp. Zool., 67: 217-281.
EDMONDS,
€
W.
I
.1950 Pituitary, adrenal, and thyroid i n cyclopia. Arch. of
Path., 50: 727-735.
MALL, F. P. 1917 Cyclopia in the human embryo. Contr. to Embr., no. 15,
Carn. Inst., Publ., no. 226: 5-33.
ROGERS,I(. T. 1952 Optic nerve pattern evidence for fusion of eye primordia
in cyclopia in Fundulus heteroclitus. J. Exp. Zool., 1CO: 287-310.
1956 Re-examination of the production of cyclopia in Fundulus
heteroelitus with magnesium chloride and ethyl alcohol. Biol. Bull.,
110: 344-351.
PLATE
PLATE
1
EXPLANATION O F FIGURES
All figures are photomicrographs of transverse sections, 10 p, modified Bodian
stain.
1 Section through cyclopean eye and posterior of telencephalon of fish 64-1.
The optic nerve can be seen leaving the eye dorsally; it onters the diencephalon
in the 6th section posterior. X 125.
2
Section through posterior of cyclopean eye and diencephalon of fish 105-1.
The optic nerve, which leaves the eye posteriorly, can be seen, cross-sectioned,
as it passes through the choroid coat. Extreme posterior extent of this eye is
in the next posterior soction, whereas the extreme posterior extent of the
eye of figure 1 is 1 7 sections posterior t o a comparable point in the
diencephalon. X 115.
3
Pituitary and ventral diencephalon of normal control fish 154-1.
4
Pituitary and ventral dicncephalon of cyclopean fish 105-1.
220
X 450.
X 450.
PLATE 1
PITUITARY IS PERFECT CYCLOPIA
I<. T . ROGERS
221
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