Proenkephalin, [Met]enkephalin, and Oxytocin Immunoreactivities are Colocalized in Bovine Hypothalamic Magnocellular Neurons

• Published in: Proceedings of the National Academy of Sciences - PNAS 1983-08, Vol.80 (16), p.5139-5143
• Main Authors: Vanderhaeghen, J. J., Lotstra, F., Liston, D. R., Rossier, J.
• Format: Article
• Language: English
• Subjects: Animals; Antiserum; Brain; Cattle; Cell nucleus; Enkephalin, Methionine - analysis; Enkephalins - analysis; Hypothalamo-Hypophyseal System - cytology; Hypothalamus - cytology; Immune Sera; Immunoassay; Neural stem cells; Neurobiology; Neurons; Neurons - analysis; Opioid peptides; Organ Specificity; Oxytocin - analysis; Posterior pituitary; Protein Precursors - analysis; Supraoptic nucleus; Supraoptic Nucleus - cytology; Ungulates
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.80.16.5139

The distribution of proenkephalin and [Met]enkephalin immunoreactivities in the bovine hypothalamo-neurohypophyseal system was studied by use of specific antisera. Proenkephalin and [Met]enkephalin immunoreactivities were found in magnocellular neuronal cell bodies in the dorsal part of the supraoptic nuclei and in the peripheral part of the paraventricular nuclei. A densely staining network of nerve terminals was found in the external part of the median eminence and in the posterior hypophysis. This general distribution is identical to that of the neurohypophyseal hormone oxytocin. The precise localization of proenkephalin and [Met]enkephalin immunoreactivities was compared to the distribution of oxytocin and vasopressin in serial 5- μ m sections through the magnocellular nuclei. Oxytocin immunoreactivity was nearly always present in cells that were stained with proenkephalin and [Met]enkephalin antisera. The vasopressin-immunoreactive cells were never stained with either the proenkephalin or the [Met]enkephalin antisera.