Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0344307 (analgesia)
 28,200 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was conducted to determine the effect of thyroid hormone on opiate receptor ligand-binding and pain sensitivity. Specific opiate receptor-binding was performed on brain homogenates of Swiss-Webster mice. There was a significant increase in 3H-naloxone-binding in thyroxine-fed subjects (hyperthyroid). Scatchard analysis revealed that the number of opiate receptors was increased in hyperthyroid mice (Bmax = 0.238 nM for hyperthyroid samples vs. 0.174 nM for controls). Binding affinity was unaffected (Kd = 1.54 nM for hyperthyroid and 1.58 nM for control samples). When mice were subjected to hotplate stimulation, the hyperthyroid mice were noted to be more sensitive as judged by pain aversion response latencies which were half that of control animals. After morphine administration, the hyperthyroid animals demonstrated a shorter duration of analgesia. These findings demonstrate that thyroxine increases opiate receptor number and native pain sensitivity but decreases the duration of analgesia from morphine.
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PMID:The effect of hyperthyroidism on opiate receptor binding and pain sensitivity. 217 66

The hypothalamic paraventricular nucleus (PVN) has been implicated in a remarkable number of functions including control of pituitary-adrenocortical activity in response to stress, body fluid homeostasis, milk ejection reflex, prolactin secretion, thyroid hormone secretion, analgesia, food intake, gastrointestinal functions, cardiovascular functions, and control of pineal melatonin synthesis. Paraventricular neurons produce hormones of key importance in neuroendocrine regulation such as vasopressin (VP), oxytocin (OX), 41-residue corticotropin releasing factor (CRF), thyrotropin releasing hormone (TRH), somatostatin (SOM) and the putative prolactin releasing factor vasoactive intestinal polypeptide (VIP). Three recent advances pertinent to the organization of the PVN include: (1) the evidence that the structure of the PVN is compartmental in nature, topographically segregated cellular units seem to carry out different functions; (2) the discovery that paraventricular neurons are capable of expressing a multitude of neuromediators simultaneously, thus cellular units can be best specified by a certain combination of neuromediators; (3) evidence that the composition of the neuromediator "cocktail" in individual neurons is variable and depends on the physiological status of the animal. Hence, the PVN may be best considered as a dynamic mosaic of chemically specified subgroups of neurons. The flexibility of neurotransmitter status in paraventricular neurons may play a central role of a functional plasticity of fixed anatomical circuits.
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PMID:Dynamism of chemoarchitecture in the hypothalamic paraventricular nucleus. 304 19