Induced Hypertrophy of Extraocular Muscles after the Administration of Synthetic Peptides Into Them
Igor L. Plisov, MD; Natalya G. Antsiferova, MD
S.N. Fyodorov IRTC “Eye Microsurgery” FSAI of the Ministry of Health Care of the Russian Federation
Novosibirsk, Russian Federation
Introduction: The purpose of the research was to conduct morphometric study of extraocular eye structures in rabbits after the introduction of synthetic peptides (SP) into them.
Methods: Morphometric research of m. rectus lateralis (MRL), m. levator palpebrae (MLP) and m. orbicularis oculi (MOO) was done in 10 experimental rabbits after the administration of SP into the periorbital area.
Results: During microscopy in the study group, the thickness of MRL and MOO muscular fibers was 30% bigger, of MLP – 56% bigger as compared with the values of this parameter in the control group.
Discussion: The hypertrophy had a non-uniform character in respect of the fiber length and was more expressed in the middle sections. It may be assumed that muscle fiber hypertrophy happens to a greater degree due to sarcoplasmic hypertrophy. Myofibrillar hypertrophy was registered only in certain MLP fibers. The most expressed differences in the compared groups were observed when assessing angiogenesis processes. The number of vessels in intramuscular space of muscle increased mainly due to hyperplastic processes with the formation of newly formed vessels of the microvasculature, exceeding the values of the similar parameter in the control group by 52.4%, which testifies to expressed stimulation of early angiogenesis with the application of peptides with an increase in capillarization and improvement of trophic processes.
Conclusion: Administration of SP into muscle activates reparative processes expressed in heterogeneous hypertrophy of muscular fibers; activation of fibrogenesis with increased number density of fibroblasts; increased reactivity of the vessel component with neoangiogenesis activation.
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