title: Distribution of nociceptin in pancreatic islet cells of normal and diabetic rats.
abstract: OBJECTIVE
  Nociceptin has been reported to play an important role in the regulation of pancreatic exocrine secretion. Most of the studies performed on nociceptin are mainly physiological rather than morphological in nature. The present study investigated the pattern of distribution of nociceptin in the endocrine pancreas of normal and diabetic rats.
  
  
  METHODS
  Immunohistochemistry, immunofluorescence, Western blot, and double-labeled immunoelectron microscopy were used in this study. Diabetes was induced using streptozotocin (60 mg/kg body weight).
  
  
  RESULTS
  Nociceptin-immunoreactive cells were observed in the central and peripheral regions of the islets of both normal and diabetic rat pancreas. The number of nociceptin-positive cells was significantly (P < 0.05) lower in the islet of diabetic rats compared with the control. Immunofluorescence study showed that nociceptin colocalizes with insulin in pancreatic β-cells. The degree of colocalization of nociceptin with insulin was severely deranged after the onset of diabetes. Moreover, immunogold particles conjugated with either nociceptin or insulin were observed on the granules of pancreatic β-cell. The number of nociceptin-labeled colloidal gold particles was significantly lower after the onset of diabetes.
  
  
  CONCLUSIONS
  Nociceptin is present in pancreatic islets cells and colocalizes with insulin. Nociceptin may have a physiological role in the metabolism of insulin.
authors: From the Departments of *Anatomy, and †Pharmacology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates; and ‡Department of Pharmacodynamics, Semmelweis University, Budapest, Hungary.
authors: Saeed
authors: S
authors: Tariq
authors: Hameed
authors: H
authors: Rashed
authors: Syed M
authors: SM
authors: Nurulain
authors: Bright Starling
authors: BS
authors: Emerald
authors: Surya
authors: S
authors: Koturan
authors: Kornélia
authors: K
authors: Tekes
authors: Ernest
authors: E
authors: Adeghate
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D015153:Blotting, Western; D016022:Case-Control Studies; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D007150:Immunohistochemistry; D007328:Insulin / Q000378:metabolism; D007515:Islets of Langerhans / Q000378:metabolism*; D008297:Male; D018847:Opioid Peptides / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D000097629:Nociceptin
chemical_list: D015415:Biomarkers; D007328:Insulin; D018847:Opioid Peptides; D000097629:Nociceptin