Different temporal and spatial distribution of TGF-beta 1 and TGF-beta 2 in rabbit vascular tissue: potential role in normal vessel growth and maturation.
The expression of transforming growth factor beta 1 and beta 2 (TGF-beta 1 and beta 2) in aortic and venous tissue from male New Zealand White rabbits, at selected time intervals after birth, was examined by the reverse transcriptase polymerase chain reaction. Stable levels of TGF-beta 1 were found in all segments derived from the aortic arch and descending aorta at each time interval. However, increasing amounts of TGF-beta 2 transcripts were observed for the aortic arch from day 4, with peaks occurring between 1 and 6 months of age, followed by progressively decreasing levels thereafter. TGF-beta 2 transcripts in the descending aorta generally did not change significantly over time. TGF-beta transcripts manifested a significantly lower expression in the vena cava than in aortic segments. Histological analysis of the vascular tissue showed cellular hyperplasia (2.5-fold greater prevalence of nuclei per field) in the aortic arch media at 1 month of age as compared with nuclei per field at 12 months and increasing thickness of the aortic arch media with time. No significant differences in relative collagen concentrations were observed among the aortic and vena cava segments. These results suggest that these TGF-beta isoforms may participate in the physiological induction and differentiation of arterial and venous tissue during early normal vascular maturation.
López-Candales
A
A
Department of Medicine, Jewish Hospital of St Louis, Washington University School of Medicine, MO 63110, USA.
Scott
M J
MJ
Wickline
S A
SA
D000199:Actins / Q000096:biosynthesis; D000818:Animals; D001013:Aorta, Thoracic / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D015152:Blotting, Northern; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D006965:Hyperplasia; D008297:Male; D015345:Oligonucleotide Probes; D016133:Polymerase Chain Reaction; D012313:RNA / Q000096:biosynthesis; D011817:Rabbits; D014158:Transcription, Genetic; D016212:Transforming Growth Factor beta / Q000096:biosynthesis*; D014684:Venae Cavae / Q000166:cytology / Q000254:growth & development / Q000378:metabolism
D000199:Actins; D015345:Oligonucleotide Probes; D016212:Transforming Growth Factor beta; D012313:RNA