@article {Altiere572, author = {R J Altiere and J S Douglas and C N Gillis}, title = {Potassium chloride- and norepinephrine-induced contractile responses in rabbit pulmonary blood vessels.}, volume = {224}, number = {3}, pages = {572--578}, year = {1983}, publisher = {American Society for Pharmacology and Experimental Therapeutics}, abstract = {Responses to KCl and norepinephrine (NE) were examined with ring segments of right extrapulmonary artery, intrapulmonary artery and intrapulmonary vein isolated from rabbit lung. From concentration-response curves to KCl, optimal applied loads were determined to be 5 g for right extrapulmonary artery and intrapulmonary artery and 500 mg for intrapulmonary vein. Both individual and cumulative concentration-response curves to KCI and NE were performed. All gave reproducible results; however, tissues were more sensitive to cumulative addition of either contractile agent. Of three successive cumulative NE concentration-response curves, second and third curves were most reproducible in relation to both sensitivity to NE and maximal force development. Cumulative NE concentration-response curves also exhibited a triphasic pattern, consisting of an initial contractile response (10(-10) to 10(-6) M NE) followed by relaxation or reversal of contractile force development (10(-6) to 10(-4) M NE), then a second contractile response at concentrations of NE greater than 10(-4) M. This response pattern was most prominent in intrapulmonary vessels and was absent in rabbit aorta.}, issn = {0022-3565}, URL = {https://jpet.aspetjournals.org/content/224/3/572}, eprint = {https://jpet.aspetjournals.org/content/224/3/572.full.pdf}, journal = {Journal of Pharmacology and Experimental Therapeutics} }