{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,5,12]],"date-time":"2024-05-12T18:54:16Z","timestamp":1715540056658},"reference-count":0,"publisher":"Canadian Science Publishing","issue":"1","license":[{"start":{"date-parts":[[1984,1,1]],"date-time":"1984-01-01T00:00:00Z","timestamp":441763200000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/www.nrcresearchpress.com\/page\/about\/CorporateTextAndDataMining"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Can. J. Physiol. Pharmacol."],"published-print":{"date-parts":[[1984,1,1]]},"abstract":" The mean arterial blood pressure (MAP) and the sensitivity of a variety of isolated smooth muscle preparations to noradrenaline were determined in spontaneously hypertensive rats (SHR), normotensive Wistar\u2013Kyoto (WKY) rats, and a number of genetically related animals obtained by cross-breeding SHR and WKY (F1<\/jats:sub>, F2<\/jats:sub>, and F3<\/jats:sub>; and \"backcrossod\" strains BC1<\/jats:sub>(S) and BC1<\/jats:sub>(W)). The major objective of this study was to determine whether there was a clear relationship between the postsynaptic sensitivity of smooth muscle to noradrenaline and the blood pressure of the animal and, in addition, determine how neuronal uptake1<\/jats:sub> activity could modify postsynaptic sensitivity. The mean arterial blood pressure profile of the animals studied was for the 6- to 8-week animals: SHR > F1<\/jats:sub> > WKY; for the 12- to 16-week group: SHR = BC1<\/jats:sub>(S) > F1<\/jats:sub> > BC1<\/jats:sub>(W) > WKY; and for the > 52 week group: SHR > BC1<\/jats:sub>(S) = F1<\/jats:sub> > BC1<\/jats:sub>(W) > WKY [F1<\/jats:sub> obtained from SHR \u00d7 WKY; BC1<\/jats:sub>(S) = SHR \u00d7 F1<\/jats:sub>; BC1<\/jats:sub>(W) = WKY \u00d7 F1<\/jats:sub>]. With the exception of the aorta from F1<\/jats:sub> animals, the noradrenaline mean effective dose (ED50<\/jats:sub>) recorded from thoracic aortae, tail artery, portal vein, and anococcygeus tissues were not significantly different. After a 20-min pretreatment of tissues from 12- to 16-week rats (but not from 6- to 8-week rats) with 4\u2002\u00d7\u200210\u22125<\/jats:sup>\u2002M cocaine, there was a significantly greater leftward shift, as indicated by the noradrenaline ED50<\/jats:sub> before: noradrenaline ED50<\/jats:sub> after cocaine ratio, in the tail artery preparation from the SHR compared with the WKY; however, no significant differences in the ED50<\/jats:sub> ratios were noted for the thoracic aorta, the portal vein, or the anococcygeus tissues. In addition, there was a good correlation, r\u2002=\u20020.59, between the mean arterial blood pressure of the SHR and related rats, and the ED50<\/jats:sub> ratio in the tail artery preparation but less so in other tissues: portal vein, 0.09; anococcygeus, 0.33. The results from the older >52-week group of rats again revealed similar noradrenaline ED50<\/jats:sub> values for the thoracic aorta, tail artery, portal vein, and anococcygeus tissues prior to cocaine treatment, and after cocaine treatment there was, with the exception of aortic tissues, a good correlation between the mean arterial blood pressure of the rat and the noradrenaline ED50<\/jats:sub> ratio in the tail artery, r\u2002=\u20020.60; with lower r values for portal vein (0.47) and anococcygeus (0.33). The present findings indicate that innervated arterial smooth muscle, as represented by the tail artery from >52-week SHR, has an elevated postjunctional sensitivity to noradrenaline which is masked by an elevated uptake1<\/jats:sub> activity; the ED50<\/jats:sub> ratio for the tail artery preparation from the 12- to 16-week animals is also higher in the SHR than WKY, suggesting elevated uptake1<\/jats:sub> activity; but the postjunctional sensitivity, after cocaine, is similar for SHR, F1<\/jats:sub>, and WKY. No such differences, in either age group, are noted in the noninnervated thoracic aorta preparation. A comparison of the results from portal vein and anococcygeus indicates no significant differences in tissue sensitivity prior to cocaine treatment, but an elevated uptake1<\/jats:sub> activity in both portal vein and anococcygeus and elevated postjunctional sensitivity in the anococcygeus from SHR of the >52 weeks, but not the 12- to 16-weck group. Thus, elevated uptake1<\/jats:sub> activity is present at an earlier age in arterial smooth muscle from SHR than in venous or nonvascular smooth muscle, indicating selective changes occur in uptake1<\/jats:sub> in the arterial smooth muscle of the SHR prior to changes in nonarterial smooth muscle. <\/jats:p>","DOI":"10.1139\/y84-015","type":"journal-article","created":{"date-parts":[[2011,4,24]],"date-time":"2011-04-24T08:52:44Z","timestamp":1303635164000},"page":"94-100","source":"Crossref","is-referenced-by-count":7,"title":["The relationship between the elevated blood pressure of the spontaneously hypertensive rat and the chemical sensitivity of smooth muscle to adrenergic agents"],"prefix":"10.1139","volume":"62","author":[{"given":"Ismail","family":"Laher","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chris","family":"Triggle","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"155","container-title":["Canadian Journal of Physiology and Pharmacology"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/www.nrcresearchpress.com\/doi\/pdf\/10.1139\/y84-015","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2020,1,5]],"date-time":"2020-01-05T16:22:52Z","timestamp":1578241372000},"score":1,"resource":{"primary":{"URL":"http:\/\/www.nrcresearchpress.com\/doi\/10.1139\/y84-015"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1984,1,1]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1984,1,1]]}},"alternative-id":["10.1139\/y84-015"],"URL":"https:\/\/doi.org\/10.1139\/y84-015","relation":{},"ISSN":["0008-4212","1205-7541"],"issn-type":[{"value":"0008-4212","type":"print"},{"value":"1205-7541","type":"electronic"}],"subject":[],"published":{"date-parts":[[1984,1,1]]}}}