Fig. 1. Time-course of the upregulation of guanylyl cyclase ₂ mRNA induced by NMDA in cerebellar granule cells. NMDA 100 µM was added to the culture medium and the total RNA extracted at the time points indicated. The RNA was reverse transcribed using random hexamers and the amount of ₂ mRNA and 18S rRNA was determined by quantitative PCR using specific primers and probes for both. All the results were normalised against the 18S rRNA values and represent the mean ± s.e.m. of three experiments performed in triplicate. *P<0.001, significant difference from control values.