Abstract
ABSTRACT. Viable cells were isolated from a 32Pinduced rat osteogenic sarcoma by digestion with collagenase/hyaluronidase followed by centrifugation over Ficoll/Triosil. The cell preparation, which remained viable in terms of glucose consumption for at least 5 h, consisted primarily of tumor cells, the only contamination being approximately 5–10% macrophages. In the presence of 10 mM theophylline cyclic AMP levels were increased by parathyroid hormone (PTH), prostaglandins E1, E2 and F2α, isoproterenol, thyroxine and calcitonin. A range of other hormones did not significantly increase cyclic AMP levels. Only insulin caused a significant increase in cyclic GMP levels in these cells. The effect of PTH was maximal within 5 min of adding the hormone. The lowest effective concentration of PTH was 8 mU/ml and half-maximal stimulation occurred at 100 mU/ml. Responses to calcitonin were small, but agreed with the effects of the hormone on cyclic AMP levels in other systems. The relative potencies of the prostagla...
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.
