Decreased aortic contractile reaction to 5-hydroxytryptamine in rats with long-term hypertension induced by lead (Pb(2+)) exposure.
Male Wistar rats were exposed to 100ppm Pb(2+) in drinking water for 10 months. Tail blood pressure, serum 5-hydroxytryptamine (5-HT), the expression of 5-HT(2B) receptor in the aorta, the aortic response to 5-HT, and the pathologic changes of aorta were examined. The systolic blood pressure of Pb(2+) exposed group was significantly increased after 2 months of Pb(2+) exposure. After 10 months of Pb(2+) exposure, aortic contractile response to 5-HT was significantly decreased. There was no significant difference in the levels of serum 5-HT and the expression of 5-HT(2B) receptor between these two groups. The aortic media and the media-lumen ratio of Pb(2+) exposed group were significantly increased. These data suggest that long-term Pb(2+) exposure can increase blood pressure, and can alter the function and structure of aortic of rats. The decreased aortic response to 5-HT has little relation to the expression of 5-HT(2B) receptor and the serum level of 5-HT, maybe is a result of the aortic structural alteration.
Zhang
Le-Feng
LF
Department of Occupational and Environmental Health, Peking University Health Science Center, Beijing 100083, People's Republic of China.
Peng
Shuang-Qing
SQ
Wang
Sheng
S
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D015153:Blotting, Western; D006973:Hypertension / Q000139:chemically induced* / Q000503:physiopathology*; D007854:Lead / Q000097:blood; D007855:Lead Poisoning / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D009206:Myocardium / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D044403:Receptor, Serotonin, 5-HT2B / Q000096:biosynthesis; D012701:Serotonin / Q000097:blood / Q000494:pharmacology*
D044403:Receptor, Serotonin, 5-HT2B; D007854:Lead; D012701:Serotonin