Table 4. Concentrations of amino acids in plasma (nmol ml^-1) of R. sylvatica sampled before or after winter conditioning, with or without moisture restriction.

Amino acid	Late summer	Hydrated	Dehydrated
Threonine	113	1605*	1658
Cystathionine	2	18*	23†
3-Aminoisobutyric acid	6	25*	35†
Alanine	334	1348*	1414
Aspartic acid	21	86*	144†
2-Aminoadipic acid	2	6*	11†
2-Aminobutyric acid	10	26*	32†
Serine	92	248*	241
Asparagine	135	354*	496†
Citrulline	29	73*	49†
Valine	107	264*	249
Isoleucine	70	164*	142
Leucine	117	266*	234
3-Methylhistidine	8	18*	28†
Glutamic acid	63	119*	188†
Hydroxyproline	17	30*	40†
Taurine	44	69*	108†
Ornithine	59	91*	96
Phosphoethanolamine	28	37*	23†
Proline	23	30*	39†
Homocystine	1	1	3†
Lysine	135	158	130
Arginine	24	28	22
Methionine	18	18	25†
Cystine	4	4	6†
Tyrosine	44	44	51
4-Aminobutyric acid (GABA)	7	6	5
Glutamine	158	124*	112
1-Methylhistidine	4	3*	4†
Phenylalanine	51	34*	31
Tryptophan	10	6*	1†
Histidine	180	54*	91†
Glycine	286	74*	102†
β-Alanine	151	36*	84†
Total	2355	5466*	5917†

Values were determined for a single pool of plasma derived from N = 8–11 frogs in each group. Values for hydrated frogs marked with an asterisk (*) differed from corresponding value for late-summer frogs by ≥ 20%. Values for dehydrated frogs marked with a dagger (†) differed from corresponding value for hydrated frogs by ≥ 20%.