Norepinephrine, epinephrine and MHPG levels in chick brain development

In this study we determined the norepinephrine (NE), epinephrine and methox y-hydroxy-phenyl-glycol (MHPG) levels in dissected chick telencephalon, die ncephalon/mesencephalon and cerebellum in a number of stages from the late embryonic period (E16, E17, E18 and E19) and post-hatching period (P1, P2, P3, P4, P5, P15 and P30) using HPLC coupled with a coulometric detection sy stem. A mobile phase which permits the detection of NE, epinephrine and MHP G simultaneously is also described. During development, NE levels increase dramatically after hatching in all brain structures studied and are not cor related in the same period with an increase in the MHPG/NE ratio. The value s obtained for epinephrine and MHPG were significantly lower than the NE va lues in all the structures and stages studied. Our results support the noti on of a specific role for NE during the first days after hatching. (C) 2001 Elsevier Science Ltd. All rights reserved.