Objective—To determine plasma concentrations of
adrenocorticotrophic hormone (ACTH) and
α-melanocyte stimulating-hormone (α-MSH) in
healthyferrets and ferrets with hyperadrenocorticism.
Animals—16 healthy, neutered, privately owned ferrets,
28 healthy laboratory ferrets (21 sexually intact
and 7 neutered), and 28 ferrets with hyperadrenocorticism.
Procedures—Healthy ferrets were used for determination
of reference plasma concentrations of ACTH
and α-MSH. Diagnosis of hyperadrenocorticism was
made on the basis of history, clinical signs, urinary
corticoid-to-creatinine ratios, ultrasonography of the
adrenal glands, and macroscopic or microscopic evaluation
of the adrenal glands. Blood samples were collected
during isoflurane anesthesia. Plasma concentrations
of ACTH and α-MSH were measured by
Results—Plasma concentrations of ACTH in 23
healthy neutered ferrets during the breeding season
ranged from 4 to 145 ng/L (median, 50 ng/L).
Plasma concentrations of α-MSH in 44 healthy
neutered or sexually intact ferrets during the breeding
season ranged from < 5 to 617 ng/L (median, 37
ng/L). Reference values (the central 95% of the values)
for ACTH and α-MSH were 13 to 100 ng/L and
8 to 180 ng/L, respectively. Plasma concentrations
of ACTH and α-MSH in ferrets with hyperadrenocorticism
ranged from 1 to 265 ng/L (median, 45
ng/L) and 10 to 148 ng/L (median, 46 ng/L), respectively.
These values were not significantly different
from those of healthy ferrets. Plasma ACTH concentrations
of sexually intact female ferrets in
estrus were significantly higher than those of
Conclusions and Clinical Relevance—Ferrets
with hyperadrenocorticism did not have
detectable abnormalities in plasma concentrations
of ACTH or α-MSH. The findings suggest
that hyperadrenocorticism in ferrets is an ACTH
and α-MSH-independent condition.—(Am J Vet
Objective—To evaluate plasma concentrations of growth hormone (GH) and insulin-like growth factor I (IGF-I) in healthy dogs and large-breed dogs with dilated cardiomyopathy (DCM).
Animals—8 dogs with DCM and 8 healthy control dogs of comparable age and body weight.
Procedures—Blood samples for determination of the pulsatile plasma GH profile were collected from all dogs at 10-minute intervals between 8:00 am and 8:00 pm. Plasma IGF-I concentration was determined in the blood sample collected at 8:00 am.
Results—No significant differences in plasma IGF-I concentrations, basal plasma GH concentration, GH pulse frequency, area under the curve above the zero line and above the baseline for GH, and GH pulse amplitude were found between dogs with DCM and control dogs.
Conclusions and Clinical Relevance—Results did not provide evidence for an association between DCM in dogs and a reduction in plasma concentrations of GH or IGF-I. Therefore, reported positive effects of GH administration are most likely attributable to local effects in the heart.
Objective—To investigate the physiologic endocrine effects of food intake and food withholding via measurement of the circulating concentrations of acylated ghrelin, growth hormone (GH), insulin–like growth factor-I (IGF-I), glucose, and insulin when food was administered at the usual time, after 1 day's withholding, after 3 days' withholding and after refeeding the next day in healthy Beagles.
Animals—9 healthy Beagles.
Procedures—Blood samples were collected from 8:30 AM to 5 PM from Beagles when food was administered as usual at 10 AM, after 1 day's withholding, after 3 days' withholding, and after refeeding at 10 AM the next day.
Results—Overall mean plasma ghrelin concentrations were significantly lower when food was administered than after food withholding. Overall mean plasma GH and IGF-I concentrations did not differ significantly among the 4 periods. Circulating overall mean glucose and insulin concentrations were significantly higher after refeeding, compared with the 3 other periods.
Conclusions and Clinical Relevance—In dogs, food withholding and food intake were associated with higher and lower circulating ghrelin concentrations, respectively, suggesting that, in dogs, ghrelin participates in the control of feeding behavior and energy homeostasis. Changes in plasma ghrelin concentrations were not associated with similar changes in plasma GH concentrations, whereas insulin and glucose concentrations appeared to change reciprocally with the ghrelin concentrations.