Fig. 1.

Effect of CGRP on basal purine level in the rat dura mater. Left and right hemiskull halves were pre-treated in parallel for 2 h without (–) and with (+) 1 μM CGRP and subsequently equilibrated for 20 min in basal salt solution in the absence of any treatment. Basal concentrations of extracellular a ATP (n = 22), b ADP (n = 22), c AMP (n = 15), and d adenosine (Ado) (n = 20) hemiskull preparations were determined by using appropriate bioluminescent or fluorometric enzyme-coupled assays and expressed as nanomoles per liter (mean ± SEM). *p < 0.05, determined by Student’s t test (paired, two-tailed)