Table 1.

Physiologically Important Acid-Base Variables, and Their Concentrations, in Arterial Plasma and Skeletal Muscle of Humas at Rest

	Plasma		Skeletal muscle
Dependent variables	Normal value	Normal range	Normal value	Normal rangec
[H+] nanoEq/L	40	33–45	100	71–126
pH	7.40	7.35–7.48	7.0	6.90–7.15
[HCO3−] mEq/L	28	22–34	10	8–12
pCO2 mmHg	40	35–45	45	40–50
[total CO2] mmol/L	30	23–36	10a	8–12a
[SID] mEq/L	40	37–43	110c	60–130
Strong ions
[Na+] mEq/L	140	132–146	15	8–30
[K+] mEq/L	3.7	2.7–4.7	140	110–165
[Ca2+] mEq/L	2.5	2–3	0.4	0.2–1.0
[Mg2+] mEq/L	1.0	0.5–2.0	5	3–7
[Cl−] mEq/L	105	99–109	10	5–25
[lactate−] mEq/L	1.0	0.5–1.5	1.5	1.0–2.0
[PCr2−] mEq/L	Na	Na	50	45–60
[SO42−] mEq/L	0.5	0.3–0.7	–	–
	Plasma		Skeletal muscle
Weak ions	Normal value	Normal range	Normal value	Normal rangec
[Atot] mEq/L	12d	11–13	140	120–170
[plasma protein] g/L	70	60–85	Na	Na
[albumin] g/L	45	30–50	Na	Na
[globulins] g/dL	25	20–35	Na	Na
[HPO42−] + [H2PO4−] mmol/L	2.7	2.0–3.5	8	7–9
Carnosine mmol/L	Na	Na	6	3–9
Protein histidine concentration mmol/L	–	–	46	30–60

^aSahlin (265).

^bHultman and Sahlin (138)

^cLindinger (174) and Lindinger and Heigenhauser (176).

^dFigge et al. (69).