Direct effects of serotonin and ketanserin on the functional morphology of embryonic chick skin in vitro.

Different organotypical culture methods are used to test direct effects of serotonin and ketanserin, a S2, alpha 1, and H1 receptor antagonist in vascular tissue, on fibroblasts and epidermal cells of embryonic chick skin in vitro. From light microscopic and electron microscopic analyses, we learn that serotonin enhances keratinization and differentiation, whereas ketanserin reduces differentiation in comparison to the control cultures. Incorporation data of fragments cultured with [3H]thymidine show that ketanserin, within a dose range from 0.05 to 5 micrograms/ml, stimulates proliferation. Serotonin at a concentration of 10 micrograms/ml slightly slows down proliferation, whereas lower doses of 0.1 and 1 microgram/ml result in tritium activities that do not differ from control cultures.