ISSN:
0021-9541
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
Fibroblast Growth Factor (FGF) stimulates quiescent Swiss 3T3 cells to initiate DNA synthesis and divide. Cells begin to enter the S-phase after a lag of 13-15 hr, and the rate of initiation of DNA synthesis in the population can be quantified by a first order rate constant, k. A subsaturating concentration of FGF may establish the lag phase, while the value of k is dependent on the FGF concentration present during the second half of the lag phase. Insulin and hydrocortisone enhance the effect of FGF by increasing k without changing the lag phase, and they can act when added at any time after FGF. Prostaglandin E1 (PGE1) causes a decrease in k and a lengthening of the lag phase, and acts only when added during the first 8 hr. None of these agents stimulate DNA synthesis in the absence of FGF.These results show that the stimulation of growth by FGF follows the same basic pattern as was previously shown with Prostaglandin F2α (PGF2α). However, since hydrocortisone inhibits stimulation by PGF2α when added during the first 4 hr of the lag phase, there are clearly differences in some events stimulated by the two growth factors.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcp.1041030112
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