[Effect of hypoxia and carbon monoxide on rat pulmonary arterial smooth muscle cell].
OBJECTIVE
To investigate the effect of carbon monoxide on rat pulmonary arterial smooth muscle cell (VSMC).


METHODS
Three groups were randomly divided, (1) Normoxia group(N), (2) Hypoxia group(H), (3) 3% CO + 1% O2 group (CO + H), then tested by immunocytochemical analysis 3H-TdR in incorporation.


RESULTS
(1) Hypoxia initiated the chang of VSMC from contractile phenotype to synthetic phenotype, the endoplasmic reticulum became dilated, the mitochondria became swollen and myelin figure appeared. alpha-actin and muscle fiber decreased. The form of VSMC in CO + H was similar to that in N. (2) Intracellular Ca2+ level of VSMC in H [4 h, 8 h, 12 h, 24 h, 36 h were (382.00 +/- 37.92) mmol/L, (456.00 +/- 53.76) mmol/L, (517.00 +/- 47.34) mmol/L, (608.00 +/- 35.92) mmol/L, (567.00 +/- 46.72) mmol/L, respectively] increased significantly(P < 0.01) than in N[4 h was(319.00 +/- 47.45) mmol/L], but that in CO + H increased slightly. (3) cAMP and cGMP level of VSMC in H increased significantly, cAMP of VSMC in CO + H increased significantly [2 h, 8 h, 12 h, 24 h were (1.87 +/- 0.36) pmol/mg protein, (2.16 +/- 0.36) pmol/mg protein, (2.36 +/- 0.41) pmol/mg protein, (2.12 +/- 0.39) pmol/mg protein, respectively] but cGMP of VSMC in CO + H increased slightly[2 h, 8 h, 12 h, 24 h were (0.52 +/- 0.21) pmol/mg protein, (0.58 +/- 0.21) pmol/mg protein, (0.60 +/- 0.24) pmol/mg protein, (0.68 +/- 0.29) pmol/mg protein, respectively].


CONCLUSIONS
Hypoxia may promote the proliferation of VSMC by second messenger system and CO in low desities can depress the action of hypoxia partly by Ca(2+)-cGMP system or by the expression of E2F-1 gene.
Wang
G
G
Institute of Respiratory Disease, Xinqiao Hospital, Third Military Medical University, Changqing 400037, China.
Qian
G
G
Mao
B
B
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002248:Carbon Monoxide / Q000494:pharmacology*; D015687:Cell Hypoxia; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D006152:Cyclic GMP / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D011651:Pulmonary Artery / Q000166:cytology; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar
D002248:Carbon Monoxide; D000242:Cyclic AMP; D006152:Cyclic GMP; D002118:Calcium