Table 1. Cytokine content in the pleural cavity 4 hr after intrapleural injection of carrageenan.

Treatment	IL-10 (pg/ml)	TNF-α (pg/ml)	MCP-1 (ng/ml)
4 hr
Vehicle-treated young rats	37·5 ± 22·1	1·2 ± 0·1	0·3 ± 0·1
Carrageenan-treated young rats	388·1 ± 31·2**	3093·1 ± 356·2**	329·1 ± 34·3**
Vehicle-treated old rats	75·2 ± 19·3	1·1 ± 0·2	0·5 ± 0·1
Carrageenan-treated old rats	116·5 ± 11·6**§	1745·2 ± 251·1**§	304·1 ± 9·6**
24 hr
Vehicle-treated young rats	10·0 ± 7·0	2·0 ± 0·5	0·2 ± 0·1
Carrageenan-treated young rats	135·7 ± 24·2*	5·3 ± 1·0*	27·0 ± 2·7*
Vehicle-treated old rats	12·0 ± 10·1	1·9 ± 0·6	0·2 ± 0·1
Carrageenan-treated old rats	41·9 ± 24·2§	2·3 ± 0·5§	21·0 ± 4·7*

IL-10, interleukin-10; TNF-α, tumour necrosis factor-α; MCP-1, monocyte chemotactic protein-1.

IL-10 and TNF-α exudate levels in carrageenan-treated old rats were significantly reduced compared with the young group at both time points. Data are mean ± standard error of mean (SEM) for five rats for each group. The Bonferroni multiple comparison test was performed, with

^**P < 0·01

^*P < 0·05 vs. vehicle-treated rats

^§P < 0·05 vs. young animals treated with carrageenan.