Comparison of serum cortisol concentrations in clinically normal dogs after administration of freshly reconstituted versus reconstituted and stored frozen cosyntropin.
OBJECTIVE
To evaluate the biological stability of reconstituted cosyntropin after storage at -20 C for 2, 4, and 6 months.


METHODS
Prospective study.


METHODS
10 clinically normal dogs.


METHODS
Serum cortisol concentrations in dogs were determined before and 1 hour after administration of freshly reconstituted cosyntropin (synthetic ACTH) or cosyntropin that had been reconstituted and stored frozen at -20 C in plastic syringes for 2, 4, and 6 months. Cosyntropin was administered at 5 micrograms/kg (2.3 micrograms/lb) of body weight, i.v.


RESULTS
Baseline serum cortisol concentrations were similar at each sampling time. Compared with the effects of freshly reconstituted cosyntropin, administration of cosyntropin that had been frozen did not have a significantly different effect on serum cortisol concentrations.


CONCLUSIONS
Cosyntropin can be reconstituted and stored frozen at -20 C in plastic syringes for 6 months with no adverse effects on bioactivity of the polypeptide.
Frank
L A
LA
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville 37901-1071, USA.
Oliver
J W
JW
D000818:Animals; D001800:Blood Specimen Collection / Q000662:veterinary*; D004283:Dog Diseases / Q000097:blood* / Q000139:chemically induced / Q000188:drug therapy; D004285:Dogs / Q000097:blood*; D007037:Hypothyroidism / Q000097:blood / Q000139:chemically induced / Q000662:veterinary*; D008297:Male; D012016:Reference Values; D012974:Sodium Iodide / Q000633:toxicity; D013972:Thyrotropin / Q000097:blood*; D013974:Thyroxine / Q000097:blood / Q000627:therapeutic use; D013997:Time Factors
D013972:Thyrotropin; D012974:Sodium Iodide; D013974:Thyroxine