A method for enriching the cadmium content of cigarette smoke and effect of exposure to this smoke on coronary vascular reactivity in the rat.
To study the effect of smoke-borne cadmium on the cardiovascular system, a method was developed to vary the cadmium content in the smoke of Kentucky 2R1 reference cigarettes. 2R1 filler tobacco was sprayed with aqueous solutions of CdSO4; cigarettes were prepared from this tobacco and smoked through Cambridge filters. These treatments increased the cadmium content of the cigarette smoke from 0.23 +/- 0.01 micrograms Cd/2R1 cigarette to 0.317 +/- 0.029, 2.38 +/- 0.092, and 4.9 +/- 0.1 micrograms Cd/cigarette for 500 microM, and 50 mM CdSO4, respectively. Male Sprague-Dawley rats were exposed for 5 or 23 weeks to smoke from 2R1 reference cigarettes and cigarettes prepared from 2R1 tobacco that was treated with 500 microM CdSO4. Following 5 weeks of smoke exposure, neither kidney cadmium amount nor coronary vascular reactivity to angiotensin was altered in either smoke-exposed group compared to cage controls or sham-smoked animals. After 23 weeks of exposure, cadmium amounts in kidneys from animals exposed to cadmium-enriched smoke were significantly greater than quantities observed in any other group. Exposure to either type of cigarette smoke increased coronary vascular reactivity above either control group. Exposure to cadmium-enriched cigarette smoke increased coronary vascular reactivity to angiotensin above the amount observed following exposure to 2R1 cigarette smoke. This finding indicates that smoke-borne cadmium may mediate the observed increases in coronary vascular reactivity following exposure to cigarette smoke.
D000704:Analysis of Variance; D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D001273:Atmosphere Exposure Chambers; D001835:Body Weight / Q000187:drug effects; D002104:Cadmium / Q000494:pharmacology*; D003331:Coronary Vessels / Q000187:drug effects; D007668:Kidney / Q000187:drug effects*; D008297:Male; D008722:Methods; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D010947:Plants, Toxic; D051381:Rats; D011919:Rats, Inbred Strains; D012907:Smoking; D014026:Nicotiana
D002104:Cadmium; D000804:Angiotensin II