Interrelations between Hypothalamic Somatostatin and Proopiomelanocortin Neurons

Somatostatin receptors were visualized by [125I]‐Tyr0‐DTrp8‐somatostatin radioautography on 35% of arcuate neurons containing proopiomelanocortin (POMC) mRNA, as identified by in situ hybridization using a [35S] labelled riboprobe on 5 μm‐thick consecutive sections. Furthermore, double immunohistochemical staining revealed contacts of β‐endorphin or α‐MSH containing fibres with a majority of somatostatin perikarya in the anterior hypothalamic periventricular nucleus. Taken together, these data indicate that hypothalamic somatostatin and POMC neurons are interconnected. The results are discussed in term of intrahypothalamic control of GH secretion.

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