The objective of the present study was to characterize some aspects of the
extracellular matrix components of the alar and septal cartilage of the nose of swine and to
examine the histological and histochemical aspects of the two types of cartilage. The
kaotropic agent Gu-HCl was used to extract the matrix components. The predominant
glycosaminoglycan in the two caitilages was chondroitin sulfate. After ultracentrifugation,
the D4 fraction of the septal and alar cartilages was fractioned on DEAE-Sephacel using na
NaCl gradient. SDS-PAGE analysiys showed similarities between the two cartilages, with
the presence of fíbromodulin, decorin and binding proteins. Only the septal cartilage
presented the 115 kDa component, which possibly appears as 30 kDa subunits after the
action of the reducing agent. The glycosaminoglycan populations were determined by
fractionation on Sepharose CL-6B followed by analysis of the samples on the agarosepolyacrilamide
gel. The two cartilages presented a strongly polydispersed population,
which was less uniformly polydispersed in the septal than in the alar cartilage. AD2
fractionation on DEAE-Sephacel and sample analysis by SDS-PAGE and agarosepolyacrylamide
electrophoresis showed the presence of the small proteoglycans biglycan
and decorin, possible associated with the large proteoglycans.
The septal cartilage presents chondrocytes roughly arranged in rows accompanyng
the widest axis of the cartilage, whereas the alar cartilage presents chondrocytes
characteristically arranged in isogenic groups. Histhochemistry was performed usisng
Xylidine Ponceau for total proteins, Picrosirius-Hematoxylin for collagen, Toluidine Blue
for total glycosaminoglycans. And alcian blues, pH 2.5 and pH 1.0, for sulfated and
carboxylated glycosaminoglycans. Total glycosaminoglycans are more cleary visible in the
territorial matrix, whereas total proteins are more cleary visible in the interterritorial matrix.
The collagen of the septal cartilage is roughly organized along the longitudinal axis of the
specimens between the chondrocytes rows.
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