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Structure and origin of the capsule of Meissner's corpuscle.

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STRUCTURE AND ORIGIN O F THE CAPSULE
O F MEISSNER’S CORPUSCLE
N. CAUNA
Department of Anatomy, Medical School, Xing’s College, Univemity
of Durham, Newcastle. upon Tyne, Elzgland
TWENTY-NINE FIGURES
INTRODUCTION
The original descriptions of the tactile corpuscle (Wagner
and hfeissner, 1852; hfeissner, 1853) make no mention of a
capsule, but since the time of Krause, Meissner’s tactile corpuscle has been classified as an encapsulated receptor. The
description of the capsule and its origin is, however, controversial, and the existence of the capsule is often questioned and even denied in the literature of the last hundred
years.
Krause (1881) suggested that all terminal corpuscles of
the peripheral nerves, including Meissner ’s corpuscle, consisted of a cellular inner bulb and a secondary sheath or
capsule derived from the perineurium. Krause’s view on
the capsule of Meissner’s corpuscle was shared by some of
his contemporaries including Thin (1873, 1874) and Merkel
(1875). Langerhans (18‘i3), however, denied the existence
of any capsule and maintained that “the heap of cells known
as the corpuscle does not even possess a separate enclosing
membrane, and the peripheral cells of the corpuscle are
directly in contact with the surrounding connective tissue.”
Langerhans was supported by Fischer (1876) and by Ranvier
(1875). The latter used his improved gold chloride technique
and studied the corpuscle in longitudinal and transverse sections. Leontowitsch ( ’01) observed that old large corpuscles
were surrounded by a membrane of connective tissue, but
77
78
N. CAUNA
the smaller corpuscles were devoid of a capsule. Heringa
( ’20) using Van-Gieson’s technique once more confirmed the
absence of the capsule describing Meissner ’s corpuscle as a
compact unit made of cells without participation of any considerable amount of fibrillar tissue.
Meanwhile, other observations were made in support of
Xrause’s view. Dogie1 (1892, ’03) using supravital methylene
blue stated that sometimes a membrane with cell nuclei could
be observed around the corpuscle. Renault (1878) described
a fibrous capsule with a space or “vaginal cavity’’ between
it and the corpuscle which he demonstrated by injection.
Lefkbure (’09) described the capsule as consisting of two
layers. The outer layer was formed of collagen fibres and
connective tissue cells ; the inner layer consisted of a delicate
lining of endothelial cells. Ruffini (’02) and Crevatin (’03)
found that the capsule of Meissner’s corpuscle was surrounded
by a reticulum of fine non-medullated nerve fibres which
formed their terminations in the capsule. This pericorpuscular reticulum is usually referred t o as Timofeew’s apparatus. Van de Velde ( ’09) using Bielschowsky’s technique
and P6rez (’31) using Cajal’s technique observed a fibrous
capsule completely surrounding the corpuscle and sometimes
sending fibrous prolongations into its interior dividing it
into lobes. Finally Rachmatulin (’36) using Golgi I1 technique found that the capsule was formed during the 6th week
after birth from the cells surrounding the corpuscle, and its
formation was essentially completed in children of 4-5 months.
He observed that the Timofeew’s apparatus of fine nerve
fibrils first appeared in children of 6 weeks.
MATERIAL AND METHODS
The material consists of human digital skin from hands of
102 individuals (male 65, female 37) ranging in age from the
last foetal month to 93 years. This material includes two
cases of degeneration of nerves: one, 27 days and the other,
76 days after the lesion. I n order to compare Meissner’s
corpuscles with other receptors in skin and mucous mem-
CAPSULE OF MEISSNER’S
CORPUSCLE
79
branes hairy skin from the hands, axilla and abdomen of 9
individuals was used, as well as mucous membranes from lip,
tongue, epiglottis and external genitalia of 7 other individuals.
The specimens were usually fixed in 10% formalin. For
morphological studies serial sections were prepared cut perpendicular and parallel to the skin surface. Sections were
cut at 3 to 1 2 p. Routine stains for cytological studies were
Harris haematoxylin and eosin, Heidenhain’s or Weigert ’s
iron haematoxylin with picro-fuchsin as counterstain, Held’s
molybdic acid haematoxylin and methylene blue. Nerve terminations were studied mostly in frozen sections (15-20 p )
cut perpendicular and parallel to the skin surface. Silver
impregnation was used as a routine nerve staining method
(20% silver nitrate 3-10 minutes, 3% formalin solution 5-10
minutes, ammoniacal silver nitrate solution 1-5 minutes, 2-3%
formalin solution 3-5 minutes, toning in approximately 0.05%
gold chloride solution). Some of the specimens stained for
nerves were treated with hyalase for 20 minutes prior to
fixation in 10% formalin (Weddell and Pallie, ’54). To demonstrate elastic fibres Gomori’s aldehyde-fuchsin technique
was used (Gomori, ’50). Unna’s orcein method for elastic
fibres and Hart’s modification of Weigert ’s elastic tissue
stain were also used as alternative methods (McClung, ’37).
OBSERVATIONS AND DISCUSSION
Relationship of Meissrzer’s corpuscle to the
surrournndirzg tissues
I n specimens prepared with cytological stains Meissner ’s
corpuscle can usually be distinguished from the surrounding
tissue of the dermal papilla, since the corpuscle or the “inner
bulb” consists of cells, but the surrounding tissue of the
dermal papilla is mainly of fibrillar connective tissue.
Polychrome methylene blue stains the corpuscle in a slightly
violet shade compared with the more greyish shade of the
connective tissue. The difference can be seen even in black
and white photographic reproductions (fig. 1).The difference
80
N. CAUNA
between the corpuscle and its surrounding tissue is still clearer
if Heidenhain’s or Weigert’s iron haematoxylin is used with
picro-fuchsin (Van Gieson) as counterstain. With this stain
the corpuscle is light brown while the surrounding papillary
tissue is bright red (fig. 2). The usual silver impregnation
methods for staining nerves do not reveal the outline of the
corpuscle (figs. 3 and 17)’ but this disadvantage can be overcome by a slight modification of the staining technique or by
overimpregnation of the section with silver (figs. 13, 14). By
a combined use of all the above methods it is possible to
ascertain that the corpuscle itself does not possess an enveloping membrane. The capsule is formed by the surrounding tissue of the papilla and is of adventitial nature, similar
to the adventitia of blood vessels. The capsule referred to
in the literature can be recognised as a condensation of the
fibrillar tissue around the corpuscle (C in figs. 1 and 2 ) and
it can be more easily distinguished if some shrinkage of the
tissues has occurred in the specimen ( S in figs. 1 and 8).
The nature of the capsule
The nature of the capsule is revealed by elastic tissue stains.
Figure 4 shows a dermal papilla with a Meissner’s corpuscle
(M) and a capillary loop (C) stained for elastic fibres. The
corpuscle has been cut transversely through its middle part.
Its elastic capsule (black in the photograph) is now clearly
visible. Figure 5 shows another dermal papilla with a Meissner’s corpuscle ( M ) and a capillary (C). The Meissner’s
corpuscle and its elastic capsule have been cut longitudinally
through their middle. Figure 6 shows a longitudinal tangential
section of a hleissner’s corpuscle and reveals the arrangement of the elastic fibrils in the capsule. Figures 4 to 6 show
that Meissner’s corpuscle is surrounded by a capsule of fine
branching elastic fibrils arranged mainly parallel to its long
axis. The size of the elastic fibrils in the capsule varies between 0.5 to 2 p in diameter. Some coarser fibrils are flattened,
measuring up to 3 p in width. The elastic fibres around
CAPSULE OF MEISSNER’S CORPUSCLE
81
Meissner’s corpuscle are fine, compared with the coarse and
ribbon-like elastic framework of the reticular layer of the
corium (fig. 7 ) . The elastic fibrils of the dermal papillae like
those of the smaller blood vessels do not stain easily. They
cannot be revealed by Weigert ’s resorcin-fuchsin method, nor
by Verhoeff’s elastic tissue stain. Unna’s orcein method for
elastic fibres is successful, if fresh synthetic orcein is used.
Hart’s modification of Weigert’s elastic tissue stain is also
satisfactory. The best method, however, is Gomori’s aldehyde-fuchsin which gives positive results with most fixatives.
I n polarised light using crossed polaroids the capsule of
Meissner’s corpuscle does not show birefringence as do the
surrounding collagen fibres of the papilla.
Attachae&
of the capsule
The capsule does not surround either the epidermal or the
corial end of Meissner’s corpuscle (fig. 5 ) . At the superficial
(epidermal) end, the elastic fibrils are interlocked with the
basal projections of the epidermal cells all around the corpuscle; by this means it is firmly anchored to the epidermis.
I n young individuals the upper end of Meissner ’s corpuscle
is directly in contact with the basal epidermal cells (fig. 5).
This can best be demonstrated in serial horizontal sections.
Later in life, in individuals approaching 20 years of age,
the corpuscle gradually descends deeper into the dermal
papilla, and serial horizontal sections of the skin show a
narrow zone of connective tissue between the basal epidermal
cells and the superficial end of the corpuscle ; the elastic capsule remains attached to the epidermis, but because of this
descent its attachment is reduced from a ring to a small
spot, so that the elastic fibrils form a short bundle or stalk
(fig. 9) before reaching the top of the corpuscle.
At the deep (corial) end of Meissner’s corpuscle, the capsule widens and splits into several strands which become
continuous with the general elastic framework of the corium,
leaving free access for the nerves approaching the corpuscle.
82
N. CAUNA
The inner aspect of the capsule is only loosely attached t o
the surface of the corpuscle. A space can often be observed
between the corpuscle and its capsule if some shrinkage has
occurred ( S in figs. 1 and 8). By means of microdissection
techniques a corpuscle can be enucleated from its capsule on
paraffin sections stained for elastic fibres. TJsing a bristle
under the microscope a single corpuscle can be enucleated,
and sweeping a whole section with a paint brush several
corpuscles may be partly or wholly dislocated.
Development of t h e capsule, appearance in old age
and following degeneratiort of n e r v e s
At birth, during the initial development of Meissner 's
corpuscle, the elastic fibres are easily demonstrated in the
reticular layer of the corium and in blood vessels, but they
are just visible (E in fig. 10) in the dermal papillae. There
is no evidence of a capsule (M in fig. lo).' During the first
and second years of life some concentration of elastic elements can be distinguished around the developing corpuscle
which fills nearly the whole of the dermal papilla leaving
little space for connective tissue around it. I n children of
5 years the capsule is clearly defined but still thin. It is fully
formed only in children approaching the 10th year of age.
I n adult life the capsule remains unchanged except for its
altered epidermal attachment described above. I n old age
the capsule does not disappear as long as the receptor persists (fig. 11). The capsule and Meissner's corpuscle persist
after degeneration of nerves. Seventy-six days after a total
evulsion of the brachial plexus no distinct change in their
shape or size was observed apart from absence of nerves
(fig. 12).
Cells of t h e capsule
Cells with elongated nuclei and deeply staining chromatin
( n in fig. 2) can be distinguished among the fibrils of the
capsule. The nuclei of the capsular cells differ from those
CAPSULE OF MEISSNER’S
CORPUSCLE
83
of Meissner’s corpuscle by their smaller size and by darker
staining chromatin (cf. n with N in fig. 2 ) . Cytological stains
do not show the cytoplasm and the shape of the capsular cells.
Silver impregnation, however, as used f o r staining nerves,
reveals the outline of the cells satisfactorily (c in figs. 13
and 14). The capsular cells have flattened cell bodies which
send branching cytoplasmic processes over the surface of
Meissner ’s corpuscle. The processes of adjacent cells sometimes join one another (fig. 14). The shape of the capsular
cells and the staining reaction of their nuclei show that they
are a variety of connective tissue cell. They are of about the
same size as fibrocytes of the dermal papillae, but smaller
than the connective tissue cells of the deeper layers of the
skin or subcutis (cf. fig. 15 with figs. 13 and 14, all of which
are reproduced at the same magnification).
Two other types of cells are occasionally found inside the
capsule in addition to fibrocytes. They are found in relation
to the nerve axons which enter the corpuscle and can best
be recognised if the nerve fibres have been stained (fig. 16).
The darker nuclei, oval in shape (S) belong to the neurilemma
(Schwann cells), the lighter elongated nuclei (H) are those
of the endoneurium (Henle’s sheath). The cells of the nerve
sheath cannot easily be distinguished from fibrocytes in specimens where nerve fibres have not been stained.
The so-called Timofeew’s apparatus
Timofeew (1896) using a vital methylene blue technique
studied various receptors in the male genitalia of mammals.
He found that each corpuscle received two types of nerve
fibres. A thick medullated axon ramified inside the corpuscle,
another much finer axon with a thin myelin sheath formed
a fine pericorpuscular network in the capsule of the receptor.
Several authors -Ruffini ( ’02) Crevatin ( ’03), Rachmatulin
(’36) later claimed to have seen the Timofeew’s apparatus in
Meissner ’s corpuscle.
The present investigation did not confirm the existence
of a pericorpuscular plexus or nerve terminations in the
84
N. CAUNA
capsule of Meissner’s corpuscle. Nerve fibres enter the corpuscle at its base or its sides. They are of different calibre,
but they all end inside it as fine horizontal networks of neurofibrils in various patterns (figs. 3, 13). Dermal papillae often
contain fine nerve fibres as well as Meissner’s corpuscles
(fig. 17) being occasionally related to their surfaces. If,
however, the fibres can be traced, it can be shown that they
form their own terminations ( T ) independent of the capsule
(figs. 17 and 18).
Function of the elastic capsule
The fact that the elastic capsule is a constant feature of
Meissner ’s corpuscle suggests that the capsule plays its
part in the function of the receptor. The epidermal attachment of the capsule facilitates the transmission of a mechanical stimulus t o the receptor because the epidermis cannot
move over the corpuscle; it secures the accuracy of stimulation because the relationship between the epidermis and the
corpuscle is maintained constant.
Meissner ’s corpuscle has a characteristic structure, well
designed for tactile discrimination (Cauna, ’54). I n the corpuscle, horizontal layers of nerve endings (figs.3, 13) are
arranged one upon another in a column. Compression of the
corpuscle along its longitudinal axis will produce simultaneous stimulation in all its layers, while oblique pressure may
bend o r displace the corpuscle without stimulation of all
elementary units. The elastic capsule facilitates the compression and expansion of the corpuscle along its longitudinal
axis, but resists any other inadequate deformation.
The comparison o f the capsule of Meissner’s
corpuscle w i t h other receptors
Hair, Pacinian corpuscle, various lingual corpuscles, genital corpuscles and receptors in the epiglottis were examined
for elastic capsules in order to compare their appearance
with those of Meissner’s corpuscle and its capsule.
CAPSULE OF MEISSNER’S
CORPUSCLE
85
The only receptor with a distinct elastic capsule comparable
with that of Meissner’s corpuscle is the hair. Figure 19 shows
a longitudinal section of a hair stained f o r nerves. The network surrounding its epithelial root sheath occupies an area
from the orifices of the sebaceous glands down to the hair
bulb, the bulb itself being devoid of a nerve plexus. Figure
20 which is another longitudinal section of a hair stained
for elastic fibres, shows that the elastic capsule surrounds
that part of the shaft of the hair which contains nerves. The
elastic capsule is not firmly attached to its epithelial sheath
(S in fig. 20).
The Pacinian corpuscle of the subcutis is devoid of an
elastic capsule. Figure 21 shows some blood vessels (V) and
their elastic elements. An elastic membrane (M) traversing
the subcutis can be seen lower down on the left. Around the
Pacinian corpuscle (P) which has been cut transversely, no
concentration of elastic fibres can be observed.
Various lingual corpuscles are shown in figures 22-24 taken
from the fungiform papilla (fig. 22)’ filiform papilla (fig.
23) and lower surface of the tongue (fig. 24). The same tissues
stained for elastic fibres are shown in figures 25-27. Figures
25 and 27 show the usual relationship of the elastic fibres
(black) and lingual corpuscles (C). Figure 26 shows a rather
exceptional concentration of elastic fibres around a corpuscle
of a filiform papilla which is, however, seldom observed.
The genital corpuscle (fig. 28) is devoid of an elastic capsule, as can be seen in figure 29. The tissue surrounding it
( G ) does not show any concentration of elastic fibrils. Various receptors in the epiglottis are also devoid of a capsule.
I n most cases they do not form compact corpuscles but form
rather loose nests of hederiform terminations.
SUMMARY
1. Meissner’s tactile corpuscle is surrounded by a n adventitial capsule derived from the tissues of the dermal papilla.
The capsule consists of fine elastic fibrils and small branching
cells of the fibrocyte variety.
86
N. C A U N A
2. The elastic fibres of the capsule are arranged mostly
parallel to the long axis of the corpuscle. Superficially, towards the skin surface, they are interlocked with the basal
projections of the epidermal cells, so supporting the attachment of Meissner’s corpuscle to the epidermis. Deeply, the
elastic fibrils become continuous with the general elastic
framework of the eorium.
3. The development of the capsule starts after birth and
its formation extends over a period of several years. The
capsule does not disappear in old age and after degeneration
of nerves.
4. Fine beaded nerve terminations are absent in the capsule of Meissner ’s corpuscle.
5. The elastic capsule of Meissner ’s corpuscle provides
a means whereby a constant relationship between the corpuscle and the epidermis is maintained and facilitates selective stimulation of the receptor.
6. Hair has an elastic capsule comparable with that of
Meissner ’s corpuscle. Pacinian corpuscle, lingual corpuscles,
genital corpuscles and various receptors in the epiglottis are
devoid of a distinct elastic capsule.
I should like to acknowledge the help and encouragement
given by Professor J. Short. My thanks are also due to Mr.
C. J. Duncan and the staff of the Photography Department
for their aid with the photographic work.
LITERATURE CITED
1954 Nature and functions of the papillary ridges of the digital
skin. Anat. Rec., 119: 449-468.
CREVATIN,F. 1903 Le terminazioni nervose nel corio della conjunctiva e della
pelle dei polpastrelli delle dita dell’uorno. Mem. della Ic. Accad. di
Sienze dell’hst. di Biol., Ser. V., 10: 409-436.
DOGIEL,A. S. 1892 Die Nervenendigungen in Meissnerschen Tastkorperchen.
Monthly Internat. Journ. of Anat. and Physiol., 9: 76-85.
1903 Ueber die Nervenapparate in der Haut des Menschen. Zeitschr. f. wiss. Zool., 75: 46-110.
FISCHER,
E. 1876 Ueber den Bau der Meissncrschen Tastkorperehen. Arch. f.
mikr. Anat., 12: 364-390.
CAUNA,N.
CAPSULE OF MEISSNER’S
CORPUSCLE
GOMORI,
G.
87
1950 Aldehyde-fuchsin: A new stain for elastic tissue. Am. J. Clin.
Path., 20: 665-666.
HERINGA,G. C. 1920 Untersuchungen iiber den Bau und die Entwicklung des
sensiblen peripheren Nervensystems. Verh. Ron. Akad. v. Wetens.
Amsterdam, 21 : 1-130.
KRAUSE,W. 1881 Die Nervenendigung innerhalb der terminalen KGrperchen.
Arch. f. mikr. Anat., 19: 53-136.
LANQERHANS,
P. 1873 Ueber Tastkorperehen und rete Malpighii. Arch. f. mikr.
Anat., 9: 730-744.
LEFBBURE,
M. 1909 Les corpuscules de Wagner-Meissner ou corpuscules du tact.
Rev. gen. d’histol., 3, fase. 11: 569-736.
LEONTOWITSCR,
A. 1901 Die Innervation der menschlichen Haut. Intern. Monatschr. f. Anat. u. Physiol., 18: 142-310.
MCCLUNG,
C. E. 1937 Handbook of Microscopical Technique. Oxford University
Press, London : Humphrey Milford. X V I I I
698 pages ; 414-415.
MEISSNER,G. 1853 Beitraege zur Anatomie und Physiologie der Haut. Leipzig.
Leopold Voss. 47 pages, 2 plates.
MERKEL,FR. 1875 Tastzellen und Tastkorperchen bei den Hausthieren und beim
Menschen. Arch. f. mikr. Anat., 11 636-652.
PBREZ,R. M. 1931 Contribution B 1’6tude des terminaisons nerveuses dans la
peau de la main. Trav. du Labor. de Recher. Biol. de L’univ. de Madrid,
27: 187-226.
Z. CH. 1936 Die Entwicklung der Meissnerschen Rarperchen in
RACHMATULIN,
der Menschenhaut. Zeitschr. f. Mikr.-anat. Forsch., 40 : 445-454.
RANVIER,L. 1875 Trait6 technique d’histologie. viii
1110 pages. Librairie
F. Savy, Paris. 917.
J. 1878 See Lef6bure.
RENAULT,
RUFFINI,A. 1902 Sull’apparato nervoso di Timofeew od apparato ultraterminale
nei corpuscoli del Meissner della cute umana. Bibliog, Anatomique,
11: 267-281.
THIN,G. 1873 Uber den Bau der Tastkorperchen. Sitzungsber. d. Wiener Akad.,
67, I11 Abt.: 130-134.
1874 On the structure of the tactile corpuscles. J. Anat. and Phys.,
8 : 30-38.
TIMOFEEW,D. 1896 Ueber eine besondere Art von eingekapselten Nervenendigungen in den miinnlichen Geschlechtsorganen bei Saugetieren. Anat.
Anz., 11 : 44-49.
VANDE VELDE,E. 1909 Die fibrillare Struktur der Nervenenden. Intern. Monatschr. f. Anat. u. Physiol., 2‘7: 225-298.
WAGNER,
R., AND G. MEISSNER 1852 Uber das Vorhandensein bisher unbekannter
eigenthiimlicher Tastkorperchen (Corpuscula tactus) in den Gefiihlswarzchen der menschlichen Haut und iiber die Endausbreitung sensitiver Nerven. Nachrichten von der Georg-August-Universi~tund der
Koniel. Gesellschaft der Wissenschaften zu Gottingen, 3 : 17-30.
WEDDELL,G., AND W. PALLIE1954 The value of ‘spreading factors’ in the
demonstration of tissue neural elements. Quart. J. Micr. Sci.. 95:
389-397
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PLATES
EXPLANATION O F PLATES
All illustrations are photomicrographs of human skin or mucous membranes.
Figurcs 1 t o 18 and figure 2 1 represent digital skin of fingers taken from the
palmar aspect of the distal phalanges. For figures reproduced at magnifications
X 1000 or X 1200 a 1.8 mm oil immersion lens was used.
PLATE 1
EXPLANATION OF FIGURES
Longitudinal section of a Meissner 's corpuscle and its surrounding tissues of
dermal papilla. The capsule ( C ) can be recognised as a condensation of
fibrillar tissue. S-space
between the corpuscle and its capsule due to
shrinkage. Middle finger. Male, 23 years. Polychrome methylene blue, 6 p.
x 1000.
Transverse section of a Meissner 's corpuscle and its surrounding tissues of
dermal papilla. The capsule (C) is of adventitial nature. It consists of fibres
and cells. The capsular cells have elongated nuclei (n) with deeply staining
chromatin. The nuclei of Meissner's corpuscle ( N ) are larger and lighter.
Middle finger. Male, 11 years. Weigert 's iron haematoxylin and picrofuchsin,
6 p . X 1000.
Transverse section of a Meissner 's corpuscle showing nerve endings. The
capsule cannot be recognised. Female, 32 years. Frozen section. Silver impregnation, 20 p. X 1200.
4 and 5
Transverse and longitudinal sections of a Meissner's corpuscle (M)
and its surrounding tissues of dermal papilla showing the elastic capsule
(black). The capillaries (C) are not surrounded by elastic fibres. Ring finger.
Male, 15 years. Gomori's aldehyde-fuchsin, lightly counterstained with
methylene blue, 9 p. X 600.
Longitudinal tangential section of a Meissner '8 corpuscle through its capsule
showing the arrangement and size of the elastic fibrils. Same specimen as
in figure 5. X 1000.
Digital skin cut across the papillary ridges perpendicularly to skin surface
showing the distribution of the elastic fibres in the corium. The papillary
layer with Meissner 's corpuscles (M) contains very fine elastic fibrils ; the
reticular layer contains coarse, often flattened fibres. Same specimen as
figure 5. X 130.
88
PLATE 1
CAPSULE O F MEISSNER’S CORPUSCLE
N. CAUNA
89
PLATE 2
ESPLANA4TION O F FIGURES
8
Transverse section of a Meissner’s corpuscle and its capsule (C). The capsule
is only loosely attached t o the corpuscle. A space (S) can be observed between
the corpuscle arid its capsule due to shrinkage. Middle finger. Male, 47 years.
Heidenhain ’s iron haematoxylin and picrofuchsin, 6 p. X 700.
9
Horizontal section of the junctional area between the epidermis and the t i p
of the dermal papilla showing the attachment ( A ) of the elastic fibrils t o
the basal epidermal cells in adult individuals. The elastic fibrils form a
short butidle or stalk before reaching the corpuscle. Compare with figure 12
which shows a deeper section of the same series. Little finger. Male, 42
years. Gomori ’s aldehyde-fuchsin, lightly counterstained with methylene blue,
5 p . x 1200.
10
Longitudinal section of a dermal papilla with a developing Meissner ’s corpuscle (Mnl. Some elastic fibres ( E ) can be distinguished in the papilla.
Meissner’s corpuscle is devoid of a capsule. Index finger. Male, 5 days.
Gomori ’s aldehyde-f uchsin, lightly counterstained with methylene blue, 5 p.
X 600.
11 Transverse section of a Meissner’s corpuscle showing t h e presence of the
elastic capsule in old age. Ring finger. Female, 93 years. Gomori’s aldehydefuchsin, lightly counterstained with methplcne blue, 8 p. X 600.
12
Transverse section of a Meissner’s corpuscle showing tho presence of the
elastic capsule after degeneration of nerves. Seventy-six days a f t e r total
evulsion of the brachial plexus no distinct change in shape or size of the
corpuscle and its capsule was observed apart from the absence of nerves.
Little finger. Male, 42 years. Gomori ’s aldehyde-fuchsin, lightly counterstxined with methylene blue, 5 p. X 1200.
13
Transverse section of a Meissner’s corpuscle showing the capsular cells (C).
They are sniall flattened fibrocytes (cf. with fig. 15) which send cytoplasmic
processes over the surface of Meissner’s corpuscle (cf. with C in fig. 14).
Index finger. Male, 9 years. Silver impregnation. Frozen section, 20 p.
X 600.
11 Transverse section of a Meissner’s corpuscle showing two capsular cells (C)
which are connected t o one another b y cytoplasmic processes. Middle finger.
Female, 21 years. Silver impregnation. Frozen section, 20 p. X 600.
15 Connective tissue cells of the corium (cf. with capsular cells of the same individual in fig. 13). Index finger. Male, 9 pears. Silver impregnation. Frozen
section, 20 p. X 600.
16 Transverse section of a Meisuim’s corpuscle showing three nerve fibres entering its interior. One of the axons describes a complete circle around the
corpuscle before entering it and losing its sheaths. S -nucleus of a Schwann
cell (neurilcmmx). I* - nucleus of Henle ’s sheath (endorieurium). Index
finger. Male, 22 ycars. Silver impregnation. Frozen section, 20 p. X 600.
17 Longitudinal section of a dermal papilla showing n Meissner’s corpuscle and
a bundle of fine ascending nerve fibres which form a subepidermal ending
( T ) independent of Meissner’s corpuscle. Ring finger. Male, 35 years. Silver
impregnation. Prior to fixation the specimen was treated with hpalase.
Frozen section, 20 p. X 600.
18 Tip of a dermal papilla showing subepidermal nerve endings of a fine axon.
Same specimen as in figure 17. X 600.
90
C A P S U L E O F MEISSNER'S CORPUSCLE
N. CAUNA
PLATE 2
PLATE 3
EXPLANATION OF FIGURES
19 Longitudinal section of a hair showing the distribution of nerve fibres around
its epithelial sheath (cf. with fig. 20). Hairy skin from the dorsal aspect
of the proximal phalanx of index finger. Male, 15 years. Silver impregnation.
Frozen section, 20p. X 124.
20
Longitudinal section of a hair showing the distribution of the elastic fibres
around i t s epithelial sheath (cf. with fig. 1 9 ) . S -space between the hair
and its elastic capsule due t o shrinkage. Axillary skin. Male, 47 pears.
Gomori’s aldehyde-fuclrsiii, 10 p. X 56.
21
Section through the deep p a r t of the corium and subcutaneous tissue of the
digital pulp slioivirig the distribution of elastic fibres. V - blood vessels of
the corium ; M - elastic membrane of the snbcutis ; F - f a t lobule ; S - sweat
gland ; P - Pacinian corpuscIe (cut transversely) devoid of an elastic capsule. Ring finger. Male, 15 ]ears. Gomori’s aldehyde-fucbsiii, 9 f i . X 100.
Figs. 22-27
Liiigual corpuscles.
Figs. 22-24 Nerves are demonstrated on frozrsi sectious (20 p ) by silver impregnation (hyalase treatment).
Figs. 25-27 Elastic fibres are shown in paraffiii seetioris (10 p ) with Gomori’b:
:ilde~iydc-fuchsiii. Female, 21 ycnrs. x 600.
22
A group of corpuscles in n fuugiform papilla from thc tip of the tongue.
33
A corpuscle in the filiform papilla.
24
A corpuscle cut transversely from the lower qurfnce of the tongue.
25
A corpusclc (‘2) in the fuiigiforni papilla from thc tip of the tongue.
26
A corpuscle (C) in tile filiforin papilla.
27
A corpuscle (C) cut transversely from the loirer surface of the tongue.
28
Longitudinal section of a genital corpuscle from glans penis. 23 years. Silver
impregnation. Frozen seetion, 20 p. X 600.
29
Longitudinal section of a genital corpuscle (G) from glans penis. E - elastic
fibres. 23 years. Gomori’s alclehyde-fuclisin, 10 p. x 600.
92
CAPSULE OF MEISSNER'S CORPUSCLE
N . CAUNA
PLATE 3
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