Journal of chemical neuroanatomy
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J. Chem. Neuroanat. · Oct 2010
Regulatory mechanism of hypothalamo-pituitary-adrenal (HPA) axis and neuronal changes after adrenalectomy in type 2 diabetes.
Diabetes, especially type 2, is closely associated with hypothalamo-pituitary-adrenal (HPA) axis regulation. Short-term effects of adrenalectomy (ADX) in type 2 diabetes are well characterized; however, there have been few reports on the long-term effects of ADX in genetically engineered type 2 diabetes and the neuroendocrine system. We performed bilateral ADX in Zucker Lean Control rats (ZLC; ADX-ZLC), Zucker Diabetic Fatty rats (ZDF; ADX-ZDF), and sham control rats to evaluate how the HPA axis would be regulated in long-term corticosterone deficient type 2 diabetic animals. ⋯ The long-termed lack of corticosterone in the blood stream is a very important factor for normal regulation of the HPA axis even in diabetic animals. From the data, we can conclude that the stimulated HPA axis regulation in the developing type 2 diabetic animals following long-term adrenalectomy has remained elevated rather than diminished. Therefore, the current study may provide useful information to better understand patients suffering from both type 2 diabetes and Addison's disease.
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J. Chem. Neuroanat. · Sep 2013
Olfactory bulbectomy induces neuronal rearrangement in the entorhinal cortex in the rat.
In humans, depression has been associated with disturbances in olfactory circuitry. Symptoms of depression can be mimicked in animals after olfactory bulbectomy (OBX). Animal models of depression-like behavior produce similar neuronal rearrangements in various brain regions as seen in patients affected by depression. ⋯ Our present results show that along with severe behavioral deficits observed in these animals, OBX considerably decreased dendritic branching and the total dendritic length in the EC, a major interface of the hippocampus and neocortical regions. The remaining cortices and NAcc were not affected by OBX. Thus, we propose that the lack of input from the olfactory bulbs resulted in serial neuronal rearrangements in the PirC, EC, and hippocampus leading, at least partially, to behavioral deficits in emotion and memory processes.
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J. Chem. Neuroanat. · Oct 2010
Early expression of injury-induced neuropeptide Y in primary sensory neurons and the cuneate nucleus in diabetic rats with median nerve transection.
In this study we examined the temporal changes in neuropeptide Y (NPY) expression in dorsal root ganglion (DRG) neurons and cuneate nucleus (CN) in streptozotocin (STZ)-induced diabetic rats with or without median nerve transection (MNT). Numerous NPY-like immunoreactive (NPY-LI) neurons and fibers were detected in the DRG and CN of the diabetic MNT (DMNT) rats respectively, but not in those with diabetes-alone. Following MNT, the time-course of NPY expression pattern in the diabetic DRG and CN was similar and both peaked at 2 weeks, which was earlier than those in the non-diabetic MNT rats. ⋯ In the diabetic CN, the number of c-Fos-LI cells also peaked at 2 weeks after MNT, which was consistent with the temporal pattern of changes in NPY expression. The results suggest that in diabetes, MNT induced NPY expression via the reduction of NT-3, and electrical stimulation of the injured median nerve evoked the release of NPY and accordingly more c-Fos-LI cells were identified in the CN. Furthermore, this study demonstrated early NPY and c-Fos expression in the diabetic rats after MNT, suggesting that the development of neuropathic signs may be advanced in hyperglycemic rats.
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J. Chem. Neuroanat. · Nov 2010
Single-prolonged stress induced mitochondrial-dependent apoptosis in hippocampus in the rat model of post-traumatic stress disorder.
Post-traumatic stress disorder (PTSD) is a stress-related mental disorder caused by experience of a traumatic event, and presents with characteristic symptoms including intrusive memories, hyperarousal, and avoidance. Recently, structural neuroimaging studies showed that hippocampal volumes were relatively low in PTSD patients. However, the mechanisms that cause such atrophy are not well understood. ⋯ Apoptotic cells were assessed by TUNEL method. Our results showed apoptotic cells were significantly increased in hippocampus of SPS rats, accompanied by release of cytochrome c from the mitochondria into the cytosol, increase of caspase-9 and caspase-3 expression and decrease of the Bcl-2/Bax ratio. The results indicate that SPS-induced apoptosis in hippocampus of PTSD rats, and the mitochondrial pathway was involved in the process of SPS-induced apoptosis.
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J. Chem. Neuroanat. · Mar 1989
Immunohistochemical evidence for different opioid systems in the rat superior cervical ganglion as revealed by imipramine treatment and receptor blockade.
The distribution pattern of opioid-immunoreactive nerve cell bodies and varicose fibres in the rat superior cervical ganglion after chronic administration of the tricyclic antidepressant imipramine, various receptor blockades (muscarinic antagonist, atropine sulphate; opiate antagonist, naloxone; kappa-antagonist, MR2266BS), and denervation was investigated immunohistochemically using a biotin-streptavidin-peroxydase complex method. Antisera to four peptides derived from two different precursors of the opioid family were used. In control superior cervical ganglia sparsely scattered nerve fibres and no neuronal cell bodies were immunoreactive when antisera to dynorphin A (1-17) or alpha-neo-endorphin (cleavage products of prodynorphin) were applied. ⋯ The preganglionic origin of the investigated fibres with prodynorphin cleavage products was concluded from the complete disappearance of such fibres after preganglionic denervation. Denervation also resulted in an increase of met-enkephalin-arg-phe- and leu-enkephalin-immunoreactive perikarya. Small intensely fluorescent (SIF) cells, which in controls were nonrea