2020, Vol.33, No.4

Anatomy & Biological Anthropology 2023 KCI Impact Factor : 0.33

pISSN : 2671-5651 / eISSN : 2671-566X
https://journal.kci.go.kr/aba

The fibularis brevis and fibularis digiti quinti muscles are of clinical significance during reconstructive surgery and treatment of fractures of the metatarsal bone. The aim of this study was to determine the morphological characteristics of these muscles and the location of their respective insertion areas. Thirty specimens from Korean cadavers were used in this study (mean age: 72.00±12.01 years). All specimens were classified into one of three types according to their morphology at the insertion site; Type 1 (single attachment), Type 2 (bifurcated attachment), and Type 3 (presence of fibularis digiti quinti muscle) were observed in 26.67% (8/30), 16.67% (5/30), and 56.67% (17/27) of cases, respectively. The location of the insertion area of the fibularis brevis muscle did not differ significantly and the width of the tendon show statistically significant difference according to the morphology. Fibularis digiti quinti muscle bellies with particularly distal attachments were observed in two specimens (6.67%). An improved understanding of the anatomical characteristics of the fibularis muscles provides insights that may benefit future anthropological study as well as clinical procedures relating to the foot.

The fibularis tertius muscle has been used by plastic surgeons during clinical procedures such as tendoplasty of the tendon graft. The aim of this study was to determine its morphological characteristics and observe its insertion area. Twenty-seven specimens from Korean cadavers were used in this study (mean age: 71.53±15.00 years). All specimens were measured and classified into four types according to their pattern and point of insertion. In 2 specimens (7.41%), fibularis tertius muscle was absent. Type I (rectangular), Type II (triangular), Type III (band), and Type IV (bifurcated) were observed in 29.63% (8/27), 25.93% (7/27), 18.52% (5/27), and 18.52% (5/27) of cases, respectively. Among the four types, the tendon of the fibularis tertius muscle in type III was mostly a proximal attachment, while those of type IV were mostly distal attachment, 3/5 of the fifth metatarsal bone. The morphology of the fibularis tertius muscle and its distal attachments were variable; therefore, precise and detailed knowledge can provide useful information to surgeons and anatomists.

Calcitonin gene-related peptide (CGRP) derived from sensory neurons contributes to the development of renal tubulointerstitial fibrosis during ureteral obstruction through upregulation of profibrotic factors. However, the mechanism by which CGRP upregulates the profibrotic factors in the ureteral obstructive setting in the kidney tubule epithelial cells is not defined. In the human kidney proximal tubule epithelial cell line, HK-2, treatment with 1 nM CGRP significantly enhanced transforming growth factor-β1 (TGF-β1) production, its release, and protein kinase C (PKC) activity. Furthermore, mechanical stretch for 6 and 24 hours significantly increased expressions of receptor activity modifying protein 1 (RAMP1) mRNA and protein among CGRP receptor components in HK-2 cells. In addition, a combination treatment with CGRP and mechanical stretch synergistically increased TGF-β1 upregulation and PKC activation. However, RAMP1 deficiency, induced by RAMP1 double nickase plasmid transfection, abolished CGRP-induced TGF-β1 upregulation and PKC activation in HK-2 cells with or without mechanical stretch. Finally, pharmacological inhibition of PKC markedly reduced TGF-β1 production and release after treatment of HK-2 cells with CGRP. Taken together, these data suggest that extraneural CGRP upregulates TGF-β1 through RAMP1-PKC axis during mechanical stretch in kidney proximal tubule epithelial cells.