Pharmacological study of signal transduction during stimulation of prothoracic glands from Manduca sexta.
نویسنده
چکیده
Cytosolic free calcium, [Ca(2+)](i), measured in individual prothoracic gland cells of Manduca sexta with Fura-2 was increased by prothoracicotropic hormone, PTTH, and by mastoparan, a wasp venom peptide, activating G proteins. The effect on [Ca(2+)](i) of mastoparan and of PTTH was inhibited by cadmium and the antagonist of T-type calcium channels, amiloride, and not influenced by the L-type calcium channel blocker nitrendipine, suggesting that the same or similar plasma membrane channels are involved in the action of mastoparan and of PTTH. Pertussis toxin prevented the mastoparan-induced increase of [Ca(2+)](i), whereas the effect of PTTH is not influenced by pertussis toxin. Intracellular addition of GDP-beta-S failed to inhibit the PTTH-stimulated increase in [Ca(2+)](i) suggesting that G proteins are not involved in the stimulatory mechanism of PTTH.
منابع مشابه
Cellular changes in the prothoracic glands of diapausing pupae of Manduca sexta.
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عنوان ژورنال:
- Journal of insect physiology
دوره 46 10 شماره
صفحات -
تاریخ انتشار 2000