Development of hypothalamic opioid neurons: A combined immunocytochemical and [ 3H]thymidine autoradiographic study

• Published in: Neuropeptides (Edinburgh) Vol. 5; no. 4; pp. 477 - 480
• Main Authors: Khachaturian, Henry, Alessi, Norman E., Lewis, Michael E., Munfakh, Nabil, Fitzsimmons, Mark D., Watson, Stanley J.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.02.1985
• Subjects: Adrenocorticotropic Hormone - metabolism; Animals; Autoradiography; Dynorphins - metabolism; Enkephalin, Leucine - metabolism; Female; Hypothalamus - cytology; Hypothalamus - embryology; Hypothalamus - metabolism; Immunoenzyme Techniques; Male; Rats; Rats, Inbred Strains; Thymidine - metabolism
• ISSN: 0143-4179; 1532-2785
• DOI: 10.1016/0143-4179(85)90058-7

Using a combined technique of immunocytochemistry and [ 3H]thymidine autoradiography, we have determined the “birth-date” of opioid peptide containing neurons in three hypothalamic nuclei. These include proopiomelanocortin neurons (indicated by ACTH immunoreactivity) in the arcuate nucleus, dynorphin a neurons in the supraoptic nucleus, and [Leu]enkephalin neurons in the periventricular nucleus. Arcuate proopiomelanocortin neurons were born very early in embryonic development, with peak heavy [ 3H]thymidine nuclear labelling occurring on embryonic day E12. Supraoptic dynorphin A neurons were also labelled relatively early (peak at E13). By contrast, [Leu]enkephalin neurons in the periventricular nucleus exhibited peak heavy nuclear labelling on day E14. The results indicate a differential genesis of these three opioid peptide containing neuronal groups in three different hypothalamic nuclei.