Partially purified extract (extract IV) of the sea anemone,
Tealia felina
was shown to have a vasoconstrictor effect on the mesenteric vessels of the rat. The potent constriction by the extract was found to be dose-related Extract IV-induced responses on the mesenteric vessels were slow and long-lasting in contrast to the brief and short-lasting response of noradrenaline. Extract IV-induced responses rose slowly to a peak and lasted much longer after (time to peak = 2.5 min; duration =12min). This response of the extract was not blocked by α-blockers, as perfusion with indoramin (10
-6M) and; phentolamine (10
-7M) blocked the responses of noradrenaline (NA) but had no effect on the extract IV - induced vasoconstrictor responses. However, indomethacin (60μg/ml) blocked the responses to extract IV.
