Biology Reference
In-Depth Information
(Hoffmann and Dorner
1975
), with BALP constituting the largest component of
TALP activity in young healthy dogs and LALP as the largest component in adult
and old dogs (Syakalima et al.
1997a
).
LALP can increase due to cholestasis caused by hepatic or extra-hepatic disease
or due to the administration of certain medications (Gaskill et al.
2004
). Serum
CALP activity is seldom detected in young or adult healthy dogs but may be found
in older dogs (Syakalima et al.
1998
). Increases in CALP occur primarily from
elevated serum cortisol levels induced by hyperadrenocorticism or iatrogenic
causes but may also occur with diabetes mellitus, hypothyroidism, hepatobiliary
disease, and chronic stress (Hoffmann et al.
1988
). Several methods have been
proposed to differentiate the isoforms of canine ALP; however, there is no gold
standard. Biochemical methods, such as levamisole inhibition, heat inactivation
(Teske et al.
1986
), and selective precipitation with lectins (Syakalima et al.
1997a
),
provide adequate separation and quantification of canine ALP isoforms (Mahaffey
and Lago
1991
). Electrophoretic methods are also used, employing various support
media, including cellulose acetate, agarose, and polyacrylamide. Samples may or
may not be pretreated with
Vibrio cholerae
neuraminidase, and affinity techniques
may be used, incorporating wheat-germ lectin (WGL) into the migration gel
(Chamberlain et al.
1992
; Bottoni et al.
2003
). The aim of this study was to compare
canine serum ALP isoform measurements from a commercially available electro-
phoresis kit [Hydragel 15 Iso-Pal (Sebia
®
)] with those from a biochemical refer-
ence method that utilized WGL precipitation and heat inactivation.
22.2 Materials and Methods
Nonfasting blood samples obtained from the cephalic vein of 40 dogs referred to the
University of Milan were placed in vacuum tubes without anticoagulant. With the
owner's written consent, surplus serum submitted for routine analysis was used.
Twenty-four male and 16 female dogs of various breeds, ranging from 6 months to
13 years of age, were used in the study. Dogs were divided into three groups: group
A - clinically normal dogs less than or equal to 1 year of age (
n
10); group B -
clinically normal dogs between 1 and less than or equal to 7 years of age (
n
¼
¼
15);
group C - dogs with untreated spontaneous hyperadrenocorticism (
n
15). Patient
health status was determined by a full physical examination, complete blood count,
and serum biochemistry profile. Spontaneous hyperadrenocorticism was diagnosed
according to the literature (Feldman and Nelson
2004
).
Upon collection, samples were immediately centrifuged at 3,000
¼
g
for 5 min,
20
C for up to 2 weeks
until analysis. TALP and ALP isoforms were measured immediately after thawing
using electrophoretic and biochemical methods (1 aliquot/method). ALP isoform
profiles were determined by a semiautomated agarose gel electrophoresis system
(Hydragel Sebia
®
PN 1210, Issy-les-Molineux, France) not previously used in
veterinary medicine, according to the manufacturer's instructions. Each aliquot
and the serum, divided into two aliquots, was stored at
