Presence of substance P positive terminals on hypothalamic somatostatinergic neurons in humans: the possible morphological substrate of the substance P-modulated growth hormone secretion.

Presence of substance P positive terminals on hypothalamic somatostatinergic neurons in humans: the possible morphological substrate of the substance P-modulated growth hormone secretion. Brain Struct Funct. 2019 Dec 05;: Authors: Luu A, Oberdoerster Z, Grignol G, Merchenthaler I, Dudas B Abstract Substance P is an undecapeptide affecting the gastrointestinal, cardiovascular, and urinary systems. In the central nervous system, substance P participates in the regulation of pain, learning, memory, and sexual homeostasis. In addition to these effects, previous papers provided solid evidence that substance P exhibits regulatory effects on growth. Indeed, our previous study revealed that growth hormone-releasing hormone (GHRH) neurons appear to be densely innervated by substance P fibers in humans. Since growth hormone secretion is regulated by the antagonistic actions of both GHRH and somatostatin, in the present paper we have examined the possibility that SP may also affect growth via the somatostatinergic system. Therefore, we have studied the putative presence of juxtapositions between the substance P-immunoreactive (IR) and somatostatinergic systems utilizing double label immunohistochemistry combined with high magnification light microscopy with oil immersion objective. In the present study, we have revealed a dense network of substance P-IR axonal varicosities contacting the majority of somatostatin-IR neurons in the human hypothal...
Source: Brain Structure and Function - Category: Neuroscience Authors: Tags: Brain Struct Funct Source Type: research