Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Binding of intrinsically labeled [3H]bradykinin was studied in isolated nephron segments of the rabbit. Highest binding was observed in the cortical collecting tubule (5.76 +/- 0.34 X 10(-18) mol/mm) and the outer medullary collecting tubule (5.24 +/- 0.25 X 10(-18) mol/mm, means +/- SE, n = 6). Small but significant binding was also seen in the glomerulus, proximal straight tubule, cortical thick ascending limb of Henle's loop, and distal convoluted tubule. Lysyl-bradykinin, methionyl-lysyl-bradykinin, and tyrosine-8-bradykinin (but not des-arginine-9-bradykinin, vasopressin, angiotensins I and II, or prostaglandins) competed with [3H]bradykinin. The site of highest kinin binding (collecting tubule) is downstream from the highest concentration of kallikrein (granular portion of distal convoluted tubule). The binding data indicate that the major sites of kinin action in the kidney are the cortical and medullary collecting tubules. One action of kinins could be the stimulation of prostaglandin synthesis in the collecting tubules, which are known to actively synthesize prostaglandins.
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PMID:Binding of [3H]bradykinin in isolated nephron segments of the rabbit. 632 16

Although intrarenal infusions of kinins produce diuresis, it is not clear to what extent this response is due to hemodynamically mediated medullary washout and/or to direct epithelial effects of kinins. Recent evidence has shown that bradykinin binds to collecting tubules in vitro. We therefore examined the interactions of lysyl-bradykinin and antidiuretic hormone (ADH) with respect to hydraulic conductivity (Lp) in the rabbit cortical collecting tubule perfused in vitro. To ensure adequate substrate for prostaglandin synthesis, the bath contained 2.5 microM arachidonic acid. Arachidonic acid produced no change in base-line Lp and had no effect on the subsequent response to a supramaximal dose of ADH (100 microU/ml). Therefore, all subsequent experiments were done in the presence of arachidonic acid. Lysyl-bradykinin (10(-9)M) added to either the lumen or bath had no effect on base-line Lp. Collecting tubules which were exposed for 1 h to bath lysyl-bradykinin (10(-9)M) had a significantly diminished subsequent Lp in response to ADH (P less than 0.02). In tubules exposed to bath lysyl-bradykinin plus indomethacin (5 microM), the subsequent ADH response was normal. Lysyl-bradykinin (10(-9)M) added to the lumen had no effect on subsequent ADH response. We conclude that lysyl-bradykinin from the basolateral side inhibits the hydroosmotic response of the cortical collecting tubule to ADH, and that this inhibition is probably prostaglandin-mediated. Lysyl-bradykinin does not affect water flow from the luminal surface. These data indicate that the diuresis seen with kinin infusions may result, at least in part, from a direct epithelial effect. They also suggest a role of the renal kallikrein-kinin system in modulating water transport in vivo.
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PMID:Interactions of lysyl-bradykinin and antidiuretic hormone in the rabbit cortical collecting tubule. 642 78