“…Thorner, Hackett, Murad & MacLeod, 1980; Ray & Wallis, 1982¿>; Merritt & Brown, 1984). Studies employing the calcium indicators Quin-2 and Fura-2 (Schofield, 1983;Koch et al 1985;Schlegel, Wuarin, Zbaren et al 1985;Hart, Ray & Wallis, 1986;Malgaroli, Vallar, Elahi et al 1987) and 45Ca2+ (Schofield & Bicknell, 1978;Schrey, Clark & Franks, 1986) have confirmed this idea. Whether this effect is associated with changes in the intracellular concentration of inositol trisphosphate is not clear and is the subject of some controversy (Brown, Baird, Quilliam et al 1985;Canónico, Jarvis, Judd & MacLeod, 1986;Enjalbert, Sladeczek, Guillon et al 1986;Journot, Hornberger, Pantaloni et al 1987).…”