Table 2.

Arterial lactate, alanine, glycerol and NEFA concentrations (µmol/L) and hepatic balance data (µmol·kg⁻¹·min⁻¹) during clamp studies

	Basal Period	Clamp Period 1			Clamp Period 2
		30 min	60 min	90 min	120 min	150 min	180 min
Arterial blood lactate
CTR	221 ± 12	248 ± 29	486 ± 60†	411 ± 46†	450 ± 27†	496 ± 25†	568 ± 65†
Bromo	270 ± 10	384 ± 63	611 ± 80†	598 ± 55*†	664 ± 74*†	712 ± 69*†	630 ± 64†
Net hepatic lactate balancea
CTR	−3.7 ± 0.6	−1.0 ± 1.3†	4.0 ± 1.3†	3.0 ± 1.5†	2.8 ± 1.5†	1.4 ± 1.3†	0.5 ± 1.4†
Bromo	−4.1 ± 0.5	0.4 ± 2.2†	4.7 ± 1.6†	3.5 ± 1.0†	1.6 ± 1.1†	0.2 ± 1.4	1.1 ± 1.1†
Arterial blood alanine
CTR	227 ± 34	235 ± 25	279 ± 27†	261 ± 24	264 ± 25	253 ± 21	250 ± 21
Bromo	246 ± 24	271 ± 33	303 ± 31†	277 ± 24	260 ± 19	255 ± 22	248 ± 12
Net hepatic alanine uptake
CTR	1.4 ± 0.3	1.2 ± 0.2	1.3 ± 0.2	1.5 ± 0.2	1.5 ± 0.3	1.7 ± 0.4	1.9 ± 0.3
Bromo	1.4 ± 0.1	1.1 ± 0.1	1.1 ± 0.2	1.2 ± 0.1	1.2 ± 0.1	1.5 ± 0.1	1.4 ± 0.1
Arterial blood glycerol
CTR	96 ± 10	46 ± 11†	35 ± 7†	33 ± 4†	34 ± 6†	26 ± 4†	21 ± 4†
Bromo	105 ± 10	53 ± 7†	46 ± 4†	47 ± 8†	46 ± 12†	44 ± 10†	33 ± 5†
Net hepatic glycerol uptake
CTR	2.1 ± 0.4	0.9 ± 0.2†	0.7 ± 0.2†	0.7 ± 0.2†	0.6 ± 0.2†	0.6 ± 0.1†	0.3 ± 0.1†
Bromo	1.7 ± 0.1	0.8 ± 0.1†	0.6 ± 0.1†	0.6 ± 0.1†	0.7 ± 0.2†	0.6 ± 0.1†	0.5 ± 0.1†
Arterial plasma NEFA
CTR	957 ± 49	394 ± 56†	243 ± 50†	149 ± 40†	85 ± 25†	96 ± 41†	104 ± 27†
Bromo	917 ± 84	249 ± 42*†	106 ± 40*†	77 ± 37†	59 ± 34†	28 ± 12†	29 ± 10†
Net hepatic NEFA uptake
CTR	2.7 ± 0.2	1.3 ± 0.4†	0.8 ± 0.3†	0.4 ± 0.1†	0.1 ± 0.3†	0.4 ± 0.3†	0.4 ± 0.1†
Bromo	3.2 ± 0.3	0.6 ± 0.4†	0.2 ± 0.1†	0.4 ± 0.2†	0.2 ± 0.2†	0.1 ± 0.0†	0.2 ± 0.8†

Data are means ± SE. Basal period values are means of 2 sampling times; controls (CTR) n = 5; group treated with bromocriptine mesylate (Bromo) n = 6. ^aNegative lactate balance data indicate net uptake. All substrates other than lactate exhibited net hepatic uptake only and are shown as positive values.

^*P < 0.05 between groups with 2 way repeated-measures ANOVA (symbols indicate time points identified as different with post hoc analysis);

^†P < 0.05 for difference from basal within the same group, using 1-way repeated-measures ANOVA (symbol indicates time points identified as different).