Summary
Phorbol ester-induced release of growth hormone (GH) and prolactin (PRL) from human somatotrophic tumors was examined in vitro. 12-O-tetradecanoyl-phorbol-13- acetate (TPA) strongly stimulated GH and PRL secretion and showed an additive effect on GH secretion if used in combination with GH releasing hormone (GHRH). In contrast, staurosporine exerted a variable inhibitory effect on GH release. There was no correlation between such effects and gsp mutations. The findings suggested that TPA doesn’t act directly through cAMP signal transduction system.
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This project was supported by the National Natural Science Foundation of China (No. 39670736) and Germany GTZ Foundation (PN93. 2254-02. 100/9517).
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Kui, L., Qin, L., Xiangjun, B. et al. The role of protein kinase C and its effect on GHRH in the regulation of hormone secretion by somatotrophinomas. Current Medical Science 20, 16–19 (2000). https://doi.org/10.1007/BF02887665
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DOI: https://doi.org/10.1007/BF02887665