BHK-mGluR1α cell monolayers were labeled withmyo-[³H]inositol (1 μCi/ml) for 48 hr and exposed to PTX (100 ng/ml) or vehicle for the last 24 hr of the labeling period. Incubations were performed in the presence of GPT (3 units/ml) plus pyruvate (5 mm) as described in Experimental Procedures. After stimulation with NaF (50 mm) plus AlCl₃ (10 μm), ionomycin (5 μm), quisqualate (30 μm), or an appropriate vehicle for 30-min incubations was terminated, and [³H]InsP₁ was extracted and separated as described in Experimental Procedures. Values are presented as mean ± standard error for three separate experiments performed in duplicate.

• ↵2-a p < 0.05.

• ↵2-b p < 0.01.