Table 3 Blood gas and electrolyte parameters (A), and levels of lactate in serum and lung tissue homogenates (B), and albumin in lung tissue homogenates (C) of LPS-challenged, vehicle-treated (LPS + vehicle); LPS-challenged, SPA4 peptide-treated (LPS + SPA4 peptide); and unchallenged and untreated C57BL6 mice. The numbers represent the mean (SEM) values derived from 6 to 16 mice per group. The p values (*p < 0.05, **p < 0.005, ***p < 0.0005, ****p < 0.0001 versus unchallenged, untreated; #p < 0.05 versus LPS + vehicle) were determined by ANOVA with Tukey’s post-hoc analysis

(A) Blood gas and electrolytes

Unchallenged, untreated

LPS + vehicle

LPS + SPA4 peptide

pCO₂ mmHg

58.44 (3.28)

79.27 (3.77)**

74 (4.36)^*

HCO₃ mmol/L

24.52 (0.61)

28.25 (0.39)*

27.48 (1.49)

tCO₂ mmol/L

26.3 (0.68)

30.68 (0.42)*

29.74 (1.60)

pO₂ mmHg

37.67 (3.77)

49.2 (4.84)

43.25 (3.30)

tHB g/dL

15.12 (0.25)

15.02 (0.25)

14.35 (0.69)

AnGAP mmol/L

14.87 (0.26)

8.91 (0.53)*

11.76 (2.21)

Base Excess (mmol/L)

3.61 (0.63)

3.11 (0.61)

3.3 (1.20)^a

Blood pH

7.267 (0.02)

7.199 (0.02)*

7.212 (0.01)

Na⁺ mmol/L

146.4 (0.53)

141.2 (0.52)****

142.6 (0.51)***

K⁺ mmol/L

4.84 (0.18)

4.10 (0.17)*

4.16 (0.17)^*

Cl⁻ mmol/L

112.3 (0.49)

108.2 (0.66)^**

108.2 (0.98)**

(B) Lactate

Unchallenged, untreated

LPS + vehicle

LPS + SPA4 peptide

In serum (pmol/μl)

3081 (190.3)

5647 (343.2)****

4684 (239.4)***, ^#

In lung (nmol/g lung)

6931 (1646)

19,420 (7108)

10,439 (2248)

(C) Albumin

Unchallenged, untreated

LPS + vehicle

LPS + SPA4 peptide

In lung (μg/g lung)

10,525 (761.1)

15,882 (997.6)***

13,451 (708.8)