Change in response with age of human articular cartilage to plasma somatomedin activity.
Normal male articular cartilage (34 specimens, age range 1--30 years) has been examined in vitro for response to somatomedin (SM) activity. Basal 3H-thymidine and 35S-sulfate incorporation both decreased with increasing age of the cartilage donor. However, enhancement of isotope incorporation which was attained on addition of 10% normal plasma (containing IU SM/ml) was greatest in cartilage from adolescents in the age range 12--17 years. The mean enhancement of 3H-thymidine incorporation (expressed as % basal) was as follows: age 1--10 years = 184 +/- 28 (SE), N = 9; 12--17 years = 436 +/- 101 (11); 18--30 years = 231 +/- 49 (8); and for 35S-sulfate incorporation was 1--10 years = 389 +/- 100 (8); 12--17 years = 824 +/- 273 (11); and 18--30 years = 572 +/- 56 (8). The increased response of cartilage in the 12--17 year group suggests that a greater sensitivity to the somatomedins may contribute to the increased skeletal growth during adolesence.
D000293:Adolescent; D000328:Adult; D000375:Aging; D002358:Cartilage, Articular / Q000187:drug effects* / Q000196:embryology / Q000378:metabolism / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D006128:Growth; D006801:Humans; D007223:Infant; D008297:Male; D012741:Sexual Maturation; D013002:Somatomedins / Q000494:pharmacology* / Q000502:physiology; D013431:Sulfates / Q000378:metabolism; D013936:Thymidine / Q000378:metabolism
D013002:Somatomedins; D013431:Sulfates; D013936:Thymidine