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Vázquez-Borrego MC, Gahete MD, Martínez-Fuentes AJ, Fuentes-Fayos AC, Castaño JP, Kineman RD, Luque RM. Multiple signaling pathways convey central and peripheral signals to regulate pituitary function: Lessons from human and non-human primate models. Mol Cell Endocrinol 2018; 463:4-22. [PMID: 29253530 DOI: 10.1016/j.mce.2017.12.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 12/14/2017] [Accepted: 12/14/2017] [Indexed: 12/12/2022]
Abstract
The anterior pituitary gland is a key organ involved in the control of multiple physiological functions including growth, reproduction, metabolism and stress. These functions are controlled by five distinct hormone-producing pituitary cell types that produce growth hormone (somatotropes), prolactin (lactotropes), adrenocorticotropin (corticotropes), thyrotropin (thyrotropes) and follicle stimulating hormone/luteinizing hormone (gonadotropes). Classically, the synthesis and release of pituitary hormones was thought to be primarily regulated by central (neuroendocrine) signals. However, it is now becoming apparent that factors produced by pituitary hormone targets (endocrine and non-endocrine organs) can feedback directly to the pituitary to adjust pituitary hormone synthesis and release. Therefore, pituitary cells serve as sensors to integrate central and peripheral signals in order to fine-tune whole-body homeostasis, although it is clear that pituitary cell regulation is species-, age- and sex-dependent. The purpose of this review is to provide a comprehensive, general overview of our current knowledge of both central and peripheral regulators of pituitary cell function and associated intracellular mechanisms, focusing on human and non-human primates.
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Affiliation(s)
- M C Vázquez-Borrego
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), 14004 Cordoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain; Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain; CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 14004 Cordoba, Spain; Agrifood Campus of International Excellence (ceiA3), 14004 Cordoba, Spain
| | - M D Gahete
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), 14004 Cordoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain; Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain; CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 14004 Cordoba, Spain; Agrifood Campus of International Excellence (ceiA3), 14004 Cordoba, Spain
| | - A J Martínez-Fuentes
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), 14004 Cordoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain; Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain; CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 14004 Cordoba, Spain; Agrifood Campus of International Excellence (ceiA3), 14004 Cordoba, Spain
| | - A C Fuentes-Fayos
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), 14004 Cordoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain; Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain; CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 14004 Cordoba, Spain; Agrifood Campus of International Excellence (ceiA3), 14004 Cordoba, Spain
| | - J P Castaño
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), 14004 Cordoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain; Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain; CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 14004 Cordoba, Spain; Agrifood Campus of International Excellence (ceiA3), 14004 Cordoba, Spain
| | - R D Kineman
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA; Jesse Brown Veterans Affairs Medical Center, Research and Development Division, Chicago, IL, USA
| | - R M Luque
- Maimonides Institute of Biomedical Research of Cordoba (IMIBIC), 14004 Cordoba, Spain; Department of Cell Biology, Physiology and Immunology, University of Cordoba, 14004 Cordoba, Spain; Reina Sofia University Hospital (HURS), 14004 Cordoba, Spain; CIBER Physiopathology of Obesity and Nutrition (CIBERobn), 14004 Cordoba, Spain; Agrifood Campus of International Excellence (ceiA3), 14004 Cordoba, Spain.
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Abstract
In the female rat, a complex interplay of both stimulatory and inhibitory hypothalamic factors controls the secretion of prolactin. Prolactin regulates a large number of physiological processes from immunity to stress. Here, we have chosen to focus on the control of prolactin secretion in the female rat in response to suckling, mating and ovarian steroids. In all three of these states, dopamine, released from neurones in the mediobasal hypothalamus, is a potent inhibitory signal regulating prolactin secretion. Early research has determined that the relief of dopaminergic tone is not sufficent to account for the full surge of prolactin secretion observed in response to the suckling stimulus, launching a search for possible prolactin-releasing factors. This research has subsequently broadened to include searching for prolactin-releasing factors controlling prolactin secretion after mating or ovarian steroids. A great deal of literature has suggested that this prolactin-releasing factor may include oxytocin. Oxytocin receptors are present on lactotrophs. These oxytocin receptors respond to exogenous oxytocin and antagonism of endogenous oxytocin inhibits lactotroph activity. In addition, the pattern of oxytocin neuronal activity and oxytocin release correlate with the release of prolactin. Here, we suggest not only that oxytocin is stimulating prolactin secretion, but also that prolactin secretion is controlled by a complex network of positive (oxytocin) and negative (dopamine) feedback loops. We discuss the available literature and attempt to describe the circuitry we believe may be responsible for controlling prolactin secretion.
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Affiliation(s)
- Jessica E. Kennett
- Department of Biology, University of Virginia, 485 McCormick Road, Charlottesville, VA 22903
| | - De’Nise T. McKee
- Department of Reproductive Medicine, University of California, San Diego, 9500 Gilman Drive, LaJolla, CA 92093-0674
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