Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030193 (pain)
 261,466 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Aquaporin 1 (AQP1) is the archetypal member of a family of water channel proteins that contribute to water homeostasis in kidney, lung, and other tissues. Although there is limited evidence that aquaporins are expressed in the nervous system, AQP4 is expressed in glia and AQP9 is present on some neuronal and glial mitochondria. In the present study, we used immunohistochemistry to show that AQP1 is heavily expressed in a population of small diameter primary sensory neurons of dorsal root, trigeminal, and nodose ganglia. AQP1 immunoreactivity is abundant in DRG cell bodies and in both the peripheral and central branches of primary afferent neurons, and colocalizes with markers of nociceptors, notably substance P and IB4. AQP1 expression in DRG is first detectable at embryonic day 15.5, which corresponds to the developmental stage when the majority of fine cutaneous afferents penetrate the dorsal horn. Electron microscopy revealed dense membrane labeling of unmyelinated axons, a few fine diameter myelinated axons, and synaptic terminals in the superficial dorsal horn. Because this restricted and dense expression suggested that AQP1 contributes to nociceptive processing, we studied behavioral responses of wildtype and AQP1 -/- mice in a comprehensive battery of acute and persistent pain tests. We also used in vivo electrophysiology in wildtype and mutant mice to measure the responses of wide dynamic range neurons in lamina V of the dorsal horn to thermal stimulation before and after noxious stimulus-induced sensitization. To date we have not detected a differential phenotype suggestive of a functional contribution of AQP1 to nociceptive processing.
Pain 2007 Sep
PMID:Anatomical and functional analysis of aquaporin 1, a water channel in primary afferent neurons. 1725 50

Aquaporin 1 (AQP1) is a member of a family of small, integral membrane water-transporting proteins, which facilitate water movement across cell membranes in response to osmotic gradients. Several papers have studied the expression and function of the AQPs in the central nervous system. However, little is known about the AQPs in the peripheral nervous system (PNS). In the PNS, AQP1, AQP2 and AQP4 have been reported in both peripheral neurons and glial cells. In this work we studied the expression and localization of AQP1 in the rat sciatic nerve. We found that from the four AQPs we studied (AQP1, AQP2, AQP4 and AQP9) only AQP1 is expressed in the nerve by reverse transcription polymerase chain reaction (RT-PCR). AQP1 is also observed at the protein level by Western blot analysis. We also studied the localization of AQP1 in the sciatic nerve by immunohistochemistry. The results show that AQP1 is present in both myelinating and non-myelinating Schwann cells. In myelin internodes AQP1 is enriched in the Schmidt-Lanterman incisures and in some internodes it is also present in the abaxonal membrane. At the nodes of Ranvier, AQP1 co-localizes with actin in the paranodal regions of the nerve. Therefore, AQP1 might play an important role in myelin homeostasis maintaining the thermodynamic equilibrium across the plasma membrane in myelinated axons during electrical activity. Also the expression of AQP1 in non-myelinating Schwann cells supports the involvement of AQP1 in pain perception.
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PMID:Localization of aquaporin 1 water channel in the Schmidt-Lanterman incisures and the paranodal regions of the rat sciatic nerve. 2545 Dec 77

Aquaporin 1 (AQP1) is a glycoprotein responsible for water passive transport quickly across biological membrane. Here, we reviewed the structural and functional impacts of AQP1 knockout (AQP1-KO) in animal or cell culture models. AQP1 gene deletion can cause a large number of abnormalities including the disturbance in epithelial fluid secretion, polyhydramnios, deficiency of urinary concentrating function, and impairment of pain perception. AQP1-KO mice also displayed aberrations of cardiovascular, gastrointestinal and hepatobiliary, and kidney functions as well as placenta and embryo development. Moreover, AQP1-KO perturbed tumor angiogenesis and led to reduced brain injury upon trauma. On the cellular level, AQP1-KO caused neuroinflammation, aberrant cell proliferation and migration, and macrophages infiltration. Mechanistic studies confirmed that AQP1 gene products regulate the secretory function and participated in balancing the osmotic water flux across the peritoneal membrane. The available data indicated that AQP1 might serve as a potential target for developing novel therapeutic approaches against diverse human diseases.
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PMID:Physiological and pathological impact of AQP1 knockout in mice. 3102 68