Figure 4

(A) Effect of reserpine and clomipramine on¹²³I-MIBG binding to primary carcinoid tumour cell cultures. Reserpine strongly reduced the ¹²³I-MIBG uptake in all cases. Clomipramine had no effect on ¹²³I-MIBG uptake in three out of four ileal carcinoids (case nos. 1, 3 and 4). In contrast, clomipramine had an inhibitory effect on ¹²³I-MIBG uptake in one ileal carcinoid (case no. 2). Values are given as mean±s.e.m. (B) Effect of reserpine and clomipramine on ¹²³I-MIBG binding to primary cell cultures of pheochromocytomas. Reserpine strongly reduced the ¹²³I-MIBG binding to all the pheochromocytomas investigated. Clomipramine also reduced the binding to three out of four pheochromocytomas (case nos. 5, 6 and 8), whereas it had no effect on the binding in case no. 7. Values are given as mean±s.e.m.