DEPLETION AND REPLETION OF ADRENAL DOPAMINE--HYDROXYLASE AFTER RESERPINE IMMUNOHISTOCHEMICAL AND FINE STRUCTURAL CORRELATES

ROSLYN FRYDMAN ¹ and LAURENCE B. GEFFEN ¹

¹ Department of Physiology, Monash University, Clayton, Victoria 3168, Australia

Immunohistochemical staining of dopamine--hydroxylase (DH) in the lamb adrenal medulla, using antibodies conjugated to horseradish peroxidase, has provided morphologic evidence that reserpine initially causes a depletion of DH protein followed by recovery within a week of the enzyme content. This corroborates biochemical evidence that increased reflex stimulation of the medulla by reserpine produces a loss of DH through exocytosis of chromaffin vesicles and that recovery is due to synthesis rather than activation of the enzyme. The ultrastructural changes observed were consistent with recent findings that chromogranins are synthesized by ribosomes in the endoplasmic reticulum and incorporated into vesicles in the Golgi apparatus. The changes in catecholamine and DH staining were not uniform throughout the medulla but were most marked in the epinephrine-containing cells near the corticomedullary junction where the cholinesterase staining was densest. This is consistent with biochemical evidence that synthesis and release of the enzyme are under both neural and hormonal control.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

Guidelines | Subscriptions | About | exPRESS - Current - Archive | Business Information | Contact

The Journal of Histochemistry & Cytochemistry is owned, published, and licensed by The Histochemical Society © 1973