Alpha 1-Acid Glycoprotein (AAG) Levels in Healthy and Pregrant Beagle Dogs

Abstract

Abstract. Serum alpha 1-acid glycoprotein (AAG) levels were measured in healthy beagles of various ages (66 male and 74 female) by turbidimetric immunoassay (TIA), and then separately -in pregnant beagles -by single radial immunodiffusion (SRID). The first experiment revealed that serum AAG levels ranged from 40 to 960 µg/ml (mean of 322 ± 202 µg/ml) in male dogs, and from 47 to 833 µg/ml -in female dogs (mean of 316 ± 199 µg/ ml), without any significant sex-or age-related variation. The second experiment, however, revealed that serum AAG levels increased in all pregnant beagles and peaked in the middle of gestation at 250-1,000 µg/ml (mean of 634 ± 246 µg/ml). In 7 of 8 dogs the AAG levels peaked about 45 days after ovulation. Despite a high value of 1,210-1,360 µg/ml being observed for serum AAG levels in 3 pregnant beagles inoculated with Staphylococcus aureus, its levels in umbilical cord blood were below the detection limit of SRID (40 µg/ml).

Serum α‐1‐acid glycoprotein concentrations in 26 dogs with pyometra

“…The mean concentration of AGP in healthy dogs was slightly higher than in previous reports, but within the same order of magnitude 12,22–26 . Differences between studies may be due to individual variation as large inter‐ and intraindividual variations in AGP concentrations have been demonstrated in people as well as in dogs within a day and between days 12,22,27,28 .…”

Pharmacokinetic and Pharmacodynamic Considerations for Drugs Binding to Alpha-1-Acid Glycoprotein

“…Wood and Wood (51) reported the same values in female non-pregnant healthy volunteers and pregnant women, however the study size was relatively small (n = 10). The opposite has been reported in the pregnant dog (25) and in rhesus monkey (59), with AAG levels about 2-fold and 4-fold higher in the pregnant animal, respectively. Given the striking differences between fetal, newborn, and adult AAG levels, it may be important to understand placental transfer and the milk to plasma ratio (M/P) for drugs that bind to AAG.…”

“…Female minipigs generally have slightly lower, though overlapping ranges, of AAG levels compared to males (19). No gender difference was observed in dog AAG levels (0.32 mg/ml) (25).…”

“…Ontogeny AAG levels range from undetectable in the developing human fetus, to 0.1-0.2 mg/ml in cord blood (47,51,53), up to 0.3 mg/ml at birth (34,51,(54)(55)(56)(57), steadily increasing to 0.4-0.7 mg/ml at 2-3 months (34,50,55), and achieving adult levels (0.6-0.9 mg/ml) by 10-12 months of age (33,34,58) (Table IV). Similarly, AAG is undetectable (<0.04 mg/ml) in the cord blood of dogs, thus significantly lower compared to adult dogs (0.32 mg/ml) (25). The opposite trend was observed in conventional pigs, with 12.7 mg/ml reported in the fetal pig, 14.3 mg/ml in 1 day newborns, 0.70 mg/ml in 4 week olds, and 0.24-0.34 mg/ml in adults (15,16).…”

“…An exception to this generalization was reported in mice, however no explanation was suggested by the authors (9). In dogs, AAG demonstrates highly variable levels (0.04-1 mg/ml) (25), though generally lower mean values (0.25-0.5 mg/ml) have been reported (26)(27)(28). There is little characterization of monkey AAG in the literature, though it has also been reported to be lower in cynomolgus monkey (0.1 mg/ml) compared to human (30).…”