Effect of cytidine diphosphate choline on growth hormone and prolactin secretion in man

The effect of intravenous infusion of cytidine diphosphate choline (CDP-choline) on the serum levels of growth hormone (GH) and prolactin (PRL) was studied in six normal adult male subjects. Serum GH levels increased and reached a maximum at 60--90 min after the initiation of infusion in all subjects examined. The mean peak value of GH in six subjects was 10.0 +/- 2.1 (mean +/- SE) ng/ml, which was signigicantly higher than the basal level (p less than 0.01). In four subjects, serum PRL levels decreased from 10--24 ng/ml to less than 7.2 ng/ml at 60--120 min, while in the other two no significant change was observed. These results indicate that CDP-choline affects GH and PRL secretion from the anterior pituitary.