Expression of hypothalamic neurohormones and their receptors in the human eye

// Sander R. Dubovy 1,3,* , Maria P. Fernandez 1,* , Jose J. Echegaray 1,5,* , Norman L. Block 3,4 , Noriyuki Unoki 1 Roberto Perez 2,4 , Irving Vidaurre 2 , Richard K. Lee 1 , Mehrdad Nadji 3 and Andrew V. Schally 2,3,4 1 Florida Lions Ocular Pathology Laboratory, Bascom Palmer Eye Institute, University of Miami, Miller School of Medicine, Miami, Florida, USA 2 Miami Veterans Affairs Medical Center, Miami, Florida, USA 3 Department of Pathology, University of Miami, Miller School of Medicine, Miami, Florida, USA 4 Divisions of Hematology/Oncology, Endocrinology, Department of Medicine, University of Miami, Miller School of Medicine, Miami, Florida, USA 5 Department of Ophthalmology, University of Puerto Rico School of Medicine, San Juan, PR, USA * These authors have contributed equally to this work Correspondence to: Andrew V. Schally, email: // Keywords : eye neuropeptides, ocular endocrinology, hormone-analog therapy Received : May 07, 2017 Accepted : May 20, 2017 Published : June 03, 2017 Abstract Extrapituitary roles for hypothalamic neurohormones have recently become apparent and clinically relevant, based on the use of synthetic peptide analogs for the treatment of multiple conditions including cancers, pulmonary edema and myocardial infarction. In the eye, it has been suggested that some of these hormones and their receptors may be present in the ciliary body, iris, trabecular meshwork and retina, but their physiological role has yet to be elucidated. Our study intends to comprehensively demonstrate the expression of some hypothalamic neuroendocrine hormones and their receptors within different retinal and extraretinal structures of the human eye. Immunofluorescence, Western blot analysis, and RT-PCR were used to evaluate the qualitative and quantitative expression of Luteinizing Hormone Releasing Hormone (LHRH), Growth Hormone Releasing Hormone (GHRH), Thyrotropin Releasing Hormone (TRH), Gastrin Releasing Peptide (GRP) and Somatostatin as well as their respective receptors (LHRH-R, GHRH-R, TRH-R, GRP-R, SST-R1) in cadaveric human eye tissue and in paraffinized human eye tissue sections. The hypothalamic hormones LHRH, GHRH, TRH, GRP and Somatostatin and their respective receptors (LHRH-R, GHRH-R, TRH-R, GRPR/BB2 and SST-R1), were expressed in the conjunctiva, cornea, trabecular meshwork, ciliary body, lens, retina, and optic nerve.