Journal of anatomy
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Vascular endothelial growth factor (VEGF) and Angiopoietins are families of vascular-specific growth factors that regulate blood vessel growth, maturation and function. To learn more about the effects of these factors in vivo, we have overexpressed VEGF-A or Angiopoietin-1 (Ang1) in two systems in mice, and examined the effects on blood vessel growth and function. In one set of studies, VEGF, Ang1, or both factors, were transgenically overexpressed in the skin under the keratin-14 (K14) promoter. ⋯ The decreased leakage was not accompanied by morphological changes. Thus, overexpressing VEGF appears to promote growth of new vessels accompanied by plasma leakage, whereas overexpressing Ang1 promotes the enlargement of existing vessels and a resistance to leakage. Further understanding of the interrelationship of these factors during normal development could lead to their application in the treatment of ischaemic diseases.
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The iliolumbar ligament has been described as the most important ligament for restraining movement at the lumbosacral junction. In addition, it may play an important role in restraining movement in the sacroiliac joints. To help understand its presumed restraining effect, the anatomy of the ligament and its orientation with respect to the sacroiliac joints were studied in 17 cadavers. ⋯ Fibre direction, length, width, thickness and orientation of the sacroiliac part of the iliolumbar ligament are described. It is mainly oriented in the coronal plane, perpendicular to the sacroiliac joint. The existence of this sacroiliac part of the iliolumbar ligament supports the assumption that the iliolumbar ligament has a direct restraining effect on movement in the sacroiliac joints.
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During surgical exposure of the carpal tunnel it is possible to injure the neurovascular structures closely related to the flexor retinaculum, such as the superficial palmar arch and the communicating branch between the ulnar and median nerves. Because of the importance of these structures and with the purpose of increasing knowledge of anatomical details concerning to their location, a biometric study was performed on the retinaculum and the communicating branch, and between the communicating branch and the distal wrist crease, as well as between the retinaculum and the superficial palmar arch. We dissected 56 hands from 28 Brazilian formalin-preserved cadavers of both sexes (24 male) at the Federal University of São Paulo-Escola Paulista de Medicina, Brazil. ⋯ The distance between the retinaculum and the superficial palmar arch in the axial line of the 4th metacarpal bone was on average 7.3 +/- 4.3 mm on the right and 8.3 +/- 3.5 mm on the left side. At the same level, the distance between the retinaculum and the communicating branch was 6.2 +/- 3.7 mm on the right side and 5.1 +/- 2.8 mm on the left. These results can be used as a reference during surgical procedures in the palmar region.
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This study provides a comparative analysis of the temporal and spatial distribution of 5 intervertebral disc (IVD) proteoglycans (PGs) in sheep. The main PGs in the 2 and 10 y old sheep groups were polydisperse chondroitin sulphate and keratan sulphate substituted species. Their proportions did not differ markedly either with spinal level or disc zone. ⋯ Versican was also diffusely distributed throughout the nucleus pulposus of fetal IVDs, and its levels were significantly lower in adult IVD specimens. This is the first study to identify versican in ovine IVD tissue sections and confirmed an earlier study which demonstrated that ovine IVD cells synthesised versican in culture (Melrose et al. 2000). The variable distribution of the PGs identified in this study provides further evidence of differences in phenotypic expression of IVD cell populations during growth and development and further demonstrates the complexity of the PGs in this heterogeneous but intricately organised connective tissue.
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The alginate bead culture system has been utilised by several groups to examine the in vitro proteoglycan (PG) metabolism of chondrocytes and intervertebral disc cells, but the nature of the PGs produced has not been examined in detail. This is largely due to the difficulty of separating the anionically charged sodium alginate support matrix from PGs which are similarly charged. In the present study ovine annulus fibrosus, transitional zone and nucleus pulposus cells were dissociated enzymatically from their respective matrices by sequential digestion with pronase/clostridial collagenase and DNAase and then cultured in alginate beads for 10 d. ⋯ Decorin and biglycan had similar distributions in the beads, being localised on the cell surface whereas versican and the 7-D-4 PG epitope were immunolocalised interterritoriarly. This study is the first to demonstrate that ovine disc cells synthesise versican in alginate bead culture. Furthermore the immunoblotting studies also showed that a proportion of the 7-D-4 PG epitope was colocalised with versican.