Vasopressin-mediated contractions in mesenteric arteries from spontaneously @entity101 XXXX : differences in response compared with @entity35 -Kyoto animals.

@entity1831 @entity101 @entity460 @entity35 @entity1063 @entity369
1. The sensitivity of mesenteric resistance arterioles to [ @entity369 ]vasopressin ( @entity1831 ) was investigated in spontaneously @entity101 @entity35 (SHR) and control @entity35 -Kyoto @entity35 (WKY). No difference in pAVP (-log dose of @entity1831 producing 50% of the maximum response) was observed [SHR 0.21 +/- 0.03 m-units/ml (n = 10) vs WKY 0.15 +/- 0.06 m-units/ml (n = 9)], although SHR vessels exhibited greater absolute tension development. 2. Both strains of @entity35 displayed tachyphylaxis to repeated stimulation with @entity1831 , and oscillatory tension changes were observed in all vessels from SHR and rarely in WKY vessels at activating concentrations of @entity1831 . 3. @entity1831 did not elicit a contractile response after @entity1063 -induced @entity460 depletion. 4. After vessels were depleted of @entity460 by using a combination of @entity460 -free media and @entity1063 stimulation, restoration of @entity460 in the presence of @entity1831 elicited a greater contractile response in SHR vessels. 5. The results therefore provide evidence for an increased @entity460 response to @entity1831 in SHR resistance vessels, although this was only demonstrable by @entity460 recovery experiments.
