Experimental studies on the regeneration of synovial membrane in rabbits
Authors
최윤구
Issue Date
1974
Description
의학과/박사
Abstract
[한글]
Experimental Studies on the Regeneration of Synovial Membrane in Rabbits
Yun Ku Choi, H.D.
Department of Medical Science Graduate School, Yonsei University
(Directed by Prof. In Hee Chung)
Over the past century a great deal of interest has been rekindled in the
regeneration of synovial membrane after synovectomy.
The regeneration of synovial membrane has been studied repeatedly by numerous
investigators in animals and membrane has been found to return to its previous form
in thirty to sixty days Sumita(1912) performed synovectomies on one knee in each of
two dogs and studied joints after synovectomies arid Sumita's two dogs are the only
first reported cartes in the literature on the conditions after synovectomies.
The mechanism of synovial regeneration following synovectomy was widely debated
during the early part of this century. It is possible that a new membrane is either
regenerated from remnants left behind at the operation or reformed by a metaplasia
of cells in the underlying tissue. Previous to the report of Key(1925), it was a
accepted general belief that regeneration of synovial membrane took place largely
as the result of extension over the denuded surface from remaining synovial pouch
tags rather than by specialization of new fibrous tissue cells.
Segale (1913) also thought regeneration occured from residual synovial cells.
However. Key(1925) and Wolcott (1927), working independently, excised varying
amounts of synovium from animal joints and studied regeneration of the membrane.
They concluded that the tissue was reconstituted in about sixty days by metaplasia
of underlying connective tissue elements in the area, rather than by ingrowth from
the remaining synovium. On the other hands, Mitchell and Cruess(1967) established
the mechanism of synovial regeneration using an autoradiographic study with
tritiated thymidine.
Mitchell and Blackwell (1969) studied ultrastructure of regenerating synovial
membrane in rabbits after subtotal synovectomy and revealed that macrophages
transformed into type A cells, fibroblasts transformed into type B cells and a new
membrane was established by thirty-five days and continued to mature until 100 days
at which time regenerated synovium could not be distinguished from the normal ender
the electron microscope.
In clinical practices, Schuller (1887) was the first who did synovectomies for
rheumatoid arthritis and Mignon (1900) reported a case of chronic traumatic
arthritis successfully treated by synovectomy.
Recently, Peterson (1968), Geens(1969), Dick et at. (1970), Goodie(1972),Patzakis
et al. (1979) and Graham et at. (1973) Performed synovectomies (or rheumatoid
arthritis independently and had demonstrated that after synovectomy the regenerated
synovium showed histological appearances suggesting a recurrence of the rheumatoid
process and an increased amount of lysosomal enzymes, as in the original diseased
membrane.
Untill the present time, histochemical studies of normal synovium in hymen and
animals have been reported by numerous investigators, but no histochemical changes
of regenerating synovial membrane in experimental animals have yet been reported in
the literature. The purpose of the present investigations is mainly to observe
histochemical changes as well as macroscopic, histological and electron microscopic
findings of regenerating synovial membrane after synovectomy.
Healthy mature rabbits weighing about 2 Kg were used as experimental animals.
Under seconal intravenous anesthesia subtotal synovectomy was carried 7ut on one
knee of the rabbit. The joint was exposed through a medial parapatellar incision
and the fat pad, suprapatellar pouch, both menisci and all available synovium were
removed. On the opposite knee of each rabbit, partial synovectomy was done. In the
cartes of partial synovectomy only the medial half of the synovium was removed and
the process of synovial membrane regeneration between subtotal and partial
synovectomized groups was compared and 5 rabbits served as normal controls. The
rabbits were sacrified by air embolism in groups of 5 at 2, 4, 8, 15, 35 and 70
days after synovectomy.
Samples of regenerating synevium were removed from the areas previously occupied
by normal synovium. For histological examinations, aerial sections were prepared
and stained with hematoxylin-eosin. To demonstrate the activity of adenosine
triphosphatase, the method presented by Wachstein and Meisel (1957) was uses. The
sections were stained by the periodic acid-Schiff method of Hotchkiss(1948) and the
malt diastase digestion method for synovial mucin. Methyl green-pyronin staining
with Lillie's method (1954) was usee for ribonucleic acid. For metachromasia, the
sections were stained with toluidine blue. Electron microscopic studies of synovium
were carried out in normal controls and 35 days after synovectomy. To observe the
influences of synovectomy on articular cartilage, articular cartilages of medial
condyle of femur were sectioned and after decalcification, paraffin blocks made,
stained with hematoxylin-eosin for histological examinations and stained with
toluidine blue for metachromasia.
The results concluded from the present studies are ;
1. Underlying connective cells began to proliferate from 2 days after
synovectomy. Four days after synovectomy, the fibroblasts had greatly increased in
number and had wondered out into the fibrin layer. Eight nays after synovectomy,
the denuded surface was begun to cover by 1-2 layers of fibroblasts incompletely
but fibroblasts were still more numerous and 15 days after synovectomy, the number
of cells had decreased great1y and synovial membrane was reconstituted to its
normal control form in 35 days after synovectomy macroscopically, histologically
and electron microscopically.
2. In normal controls, strong PAS reactions were present in cytoplasms of
synovial cells and in some places the cells appeared to be coverer by a thin band
of PAS positive materials. Two days and 4 days after synovectomy, PAS positive
materials in cytoplasms of proliferating fibroblasts were greatly decreased and 8
days after synovectomy. proliferating cells showed moderate PAS reactions. From 15
days after synovectomy, cells had strong PAS positive material in their
cytoplasms as in that of normal controls.
3. Synovial cells of normal controls showed a strong ATP-ase activity. ATP-ase
activity was markedly diminished in 2 days after synvectomy. From 4 days after
synovectomy, ATP-ase activity began to rice. From 35 days after synovectomy,
surface lining cells showed a strong ATP-ase activity and could not be
distinguished from that of normal controls.
4. With methyl green-pyronin staining for RNA, almost all synovial cells of
normal controls had few pyroninophilic granules in their cytoplasms.
Two days after synovectomy, proliferating cells showed moderate staining
reactions. Four days and 8 days after synovectomy, cells showed a definite increase
in number of pyroninop-hilic granules in their cytoplasms. From 15 dabs after
synovectomy, pyreninophilic granules of cells began to decrease and 38 days after
synovectomy, cells showed only a faint staining reactions as in that of normal
controls.
5. Toluidine blue gave only faint metachromasia to the very rarely seen masts
cells at 35 days after synovectomy and fibroblasts at 8 dabs and 15 days after
synovectomy.
6. There were no alterations in the appearances of chondrocytes throughout the
experiments, but metachromasia of articular cartilages decreased markedly from 2
days to 15 days after synovectomy. From 35 days after synovectomy, metachromasia
returned to its normal staining character.
7. In all specimens, no differences could be found between subtotal and partial
synovectomized groups in the process of synovial membrane regeneration.
It is suggested that in the Process of synovial membrane regeneration after
synovectomy, a part of the functional aspects paralell the morphological changes.
[영문]
Over the past century a great deal of interest has been rekindled in the regeneration of synovial membrane after synovectomy.
The regeneration of synovial membrane has been studied repeatedly by numerous investigators in animals and membrane has been found to return to its previous form in thirty to sixty days Sumita(1912) performed synovectomies on one knee in each of
two dogs and studied joints after synovectomies arid Sumita's two dogs are the only first reported cartes in the literature on the conditions after synovectomies.
The mechanism of synovial regeneration following synovectomy was widely debated during the early part of this century. It is possible that a new membrane is either regenerated from remnants left behind at the operation or reformed by a metaplasia of cells in the underlying tissue. Previous to the report of Key(1925), it was a accepted general belief that regeneration of synovial membrane took place largely as the result of extension over the denuded surface from remaining synovial pouch tags rather than by specialization of new fibrous tissue cells.
Segale (1913) also thought regeneration occured from residual synovial cells. However. Key(1925) and Wolcott (1927), working independently, excised varying amounts of synovium from animal joints and studied regeneration of the membrane. They concluded that the tissue was reconstituted in about sixty days by metaplasia of underlying connective tissue elements in the area, rather than by ingrowth from the remaining synovium. On the other hands, Mitchell and Cruess(1967) established the mechanism of synovial regeneration using an autoradiographic study with
tritiated thymidine.
Mitchell and Blackwell (1969) studied ultrastructure of regenerating synovial membrane in rabbits after subtotal synovectomy and revealed that macrophages transformed into type A cells, fibroblasts transformed into type B cells and a new
membrane was established by thirty-five days and continued to mature until 100 days at which time regenerated synovium could not be distinguished from the normal ender the electron microscope.
In clinical practices, Schuller (1887) was the first who did synovectomies for rheumatoid arthritis and Mignon (1900) reported a case of chronic traumatic arthritis successfully treated by synovectomy.
Recently, Peterson (1968), Geens(1969), Dick et at. (1970), Goodie(1972),Patzakis et al. (1979) and Graham et at. (1973) Performed synovectomies (or rheumatoid arthritis independently and had demonstrated that after synovectomy the regenerated
synovium showed histological appearances suggesting a recurrence of the rheumatoid process and an increased amount of lysosomal enzymes, as in the original diseased membrane.
Untill the present time, histochemical studies of normal synovium in hymen and animals have been reported by numerous investigators, but no histochemical changes of regenerating synovial membrane in experimental animals have yet been reported in the literature. The purpose of the present investigations is mainly to observe histochemical changes as well as macroscopic, histological and electron microscopic findings of regenerating synovial membrane after synovectomy.
Healthy mature rabbits weighing about 2 Kg were used as experimental animals.
Under seconal intravenous anesthesia subtotal synovectomy was carried 7ut on one knee of the rabbit. The joint was exposed through a medial parapatellar incision and the fat pad, suprapatellar pouch, both menisci and all available synovium were
removed. On the opposite knee of each rabbit, partial synovectomy was done. In the cartes of partial synovectomy only the medial half of the synovium was removed and the process of synovial membrane regeneration between subtotal and partial synovectomized groups was compared and 5 rabbits served as normal controls. The
rabbits were sacrified by air embolism in groups of 5 at 2, 4, 8, 15, 35 and 70 days after synovectomy.
Samples of regenerating synevium were removed from the areas previously occupied by normal synovium. For histological examinations, aerial sections were prepared and stained with hematoxylin-eosin. To demonstrate the activity of adenosine
triphosphatase, the method presented by Wachstein and Meisel (1957) was uses. The sections were stained by the periodic acid-Schiff method of Hotchkiss(1948) and the malt diastase digestion method for synovial mucin. Methyl green-pyronin staining
with Lillie's method (1954) was usee for ribonucleic acid. For metachromasia, the sections were stained with toluidine blue. Electron microscopic studies of synovium were carried out in normal controls and 35 days after synovectomy. To observe the
influences of synovectomy on articular cartilage, articular cartilages of medial condyle of femur were sectioned and after decalcification, paraffin blocks made, stained with hematoxylin-eosin for histological examinations and stained with toluidine blue for metachromasia.
The results concluded from the present studies are ;
1. Underlying connective cells began to proliferate from 2 days after
synovectomy. Four days after synovectomy, the fibroblasts had greatly increased in
number and had wondered out into the fibrin layer. Eight nays after synovectomy,
the denuded surface was begun to cover by 1-2 layers of fibroblasts incompletely
but fibroblasts were still more numerous and 15 days after synovectomy, the number
of cells had decreased great1y and synovial membrane was reconstituted to its
normal control form in 35 days after synovectomy macroscopically, histologically
and electron microscopically.
2. In normal controls, strong PAS reactions were present in cytoplasms of
synovial cells and in some places the cells appeared to be coverer by a thin band
of PAS positive materials. Two days and 4 days after synovectomy, PAS positive
materials in cytoplasms of proliferating fibroblasts were greatly decreased and 8
days after synovectomy. proliferating cells showed moderate PAS reactions. From 15
days after synovectomy, cells had strong PAS positive material in their
cytoplasms as in that of normal controls.
3. Synovial cells of normal controls showed a strong ATP-ase activity. ATP-ase
activity was markedly diminished in 2 days after synvectomy. From 4 days after
synovectomy, ATP-ase activity began to rice. From 35 days after synovectomy,
surface lining cells showed a strong ATP-ase activity and could not be
distinguished from that of normal controls.
4. With methyl green-pyronin staining for RNA, almost all synovial cells of
normal controls had few pyroninophilic granules in their cytoplasms.
Two days after synovectomy, proliferating cells showed moderate staining
reactions. Four days and 8 days after synovectomy, cells showed a definite increase
in number of pyroninop-hilic granules in their cytoplasms. From 15 dabs after
synovectomy, pyreninophilic granules of cells began to decrease and 38 days after
synovectomy, cells showed only a faint staining reactions as in that of normal
controls.
5. Toluidine blue gave only faint metachromasia to the very rarely seen masts
cells at 35 days after synovectomy and fibroblasts at 8 dabs and 15 days after
synovectomy.
6. There were no alterations in the appearances of chondrocytes throughout the
experiments, but metachromasia of articular cartilages decreased markedly from 2
days to 15 days after synovectomy. From 35 days after synovectomy, metachromasia
returned to its normal staining character.
7. In all specimens, no differences could be found between subtotal and partial
synovectomized groups in the process of synovial membrane regeneration.
It is suggested that in the Process of synovial membrane regeneration after
synovectomy, a part of the functional aspects paralell the morphological changes.