Abstract
ABSTRACTThe cartilaginous limb-bone rudiments of the 6-day-old embryonic chick show a differential growth response to treatment with triiodothyronine (T3) during 8 days’ culture in vitro. The growth in length and wet weight of the tibia is reduced by l · 6 × 10–4g. T3/l. of medium, but the growth of the radius is increased. Tibia and radius explanted at comparable histogenetic stages respond differently to T3, but the responses are slightly modified by the stage of development at which the rudiments are exposed to the hormone: tibiae from 5-to -day-old embryos show a transitory stimulation of growth in length, followed by retardation, while increase in the growth in length of radii from 7- and 8-day-old embryos is less than that of radii from 6-day-old embryos. Five small limb-bone rudiments of a similar size (third metatarsus, radius, ulna, third metacarpus, and fourth metacarpus) respond differentially to T3. It is therefore unlikely that the differential growth-response of the tibia and radius is a result of the limited nutritional conditions in vitro.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
