Tissue and blood gamma-glutamyl transferase distribution in the pig.

Gamma-glutamyl transferase distribution was studied in 10 pigs with an average weight of 100 kg. It was shown that kidney had the highest concentration of the enzyme, followed by pancreas, spleen and liver. Blood activities measured in plasma and sera from 54 animals were very similar, ie, 35+/-21 iu/litre for plasma and 36+/-14 iu/litre for serum.     

Diagnostic value of serum gamma-glutamyl transferase and alkaline phosphatase activities in hepatobiliary disease in the cat

The diagnostic value of serum gamma-glutamyl transferase (GGT) activity and serum alkaline phosphatase (ALP) activity in the detection of liver disease in the cat (n = 69) was compared. On the basis of histologic examination of the liver, cats were assigned to 8 groups: group 1--complete extrahepatic bile duct obstruction (n = 5), group 2--cholangiohepatitis-cholangitis syndrome (n = 11), group 3--hepatic lipidosis (n = 15), group 4--neoplasia, including lymphosarcoma and myeloproliferative disease (n = 9), group 5--hepatic necrosis (n = 7), group 6--cirrhosis (n = 3), group 7--portosystemic vascular anomaly (n = 4), and group 8--miscellaneous (n = 15). Cats assigned to group 8 lacked substantial histologic abnormalities of the liver. The mean value +/- SD of GGT in 20 clinically normal cats was 0.44 +/- 0.26 IU/L. The highest GGT activity in clinical patients developed in groups 1, 2, and 6. The highest ALP activity developed in groups 1 to 4. Significant correlations between GGT and ALP activities were detected only in groups 2 (P less than 0.001) and 5 (P less than 0.10). Among 54 cats with hepatic disease, only 11% had both the GGT and ALP activities within the normal ranges. Comparatively, 52% had ALP activities within the normal range, and 17% had GGT activities within the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)     

Tissue distribution and blood levels of gamma-glutamyl transferase in the horse.

In the horse, gamma-glutamyl transferase (GGT) was found to be mainly located in the kidneys, liver and pancreas. As renal lesions are followed by a urinary escape of enzyme, it can be assumed that if there are raised serum enzyme levels then the source will be chiefly from the liver and pancreas. In the blood, GGT can be measured either in plasma or serum. Its mean level in 58 horses was 12 U/L. This level was not affected by moderate dilution or slight haemolysis and its activity was only slightly decreased by storage at--30 degrees C. The relative hepatic specificity of this enzyme and its easy measurement make it a potentially very useful measure of liver dysfunction in the horse.     

Tissue and blood distribution of gamma-glutamyl transferase in the lamb and in the ewe.

Gamma-glutamyl transferase distribution was studied in 10 ewes and 10 lambs; in both groups kidney was the most active organ, followed by pancreas, liver and lungs. In kidney and liver, GGT was bound mainly to cellular structures. Blood GGT activity of 48 lambs was 44 +/- 11 iu/litre and 33 +/- 7 iu/litre of 45 ewes.     

Haptoglobin in the serum of thoroughbreds in training

A method is described for the measurement of haptoglobin in equine serum using the peroxidase activity of the haemoglobin-haptoglobin complex. The problems of interference with Fe2+ and Fe3+ ions are described. Normal values for haptoglobin in 629 blood samples from thoroughbreds in training are presented showing a log normal distribution with a 5 per cent to 95 per cent range of 0.42 to 1.7 g/litre. There was no consistent alteration in haptoglobin concentration throughout the season in spite of a change in red cell size and total bilirubin concentration. It is concluded that the measurement of haptoglobin is useful in the detection of frank haemolytic states but is insufficiently sensitive to detect mild red cell destruction. The test, after further investigation, might be used as an adjunct to the current batch of blood tests employed to assess liver function.     

Urinary gamma-glutamyl transferase and the degree of renal dysfunction in 75 bitches with pyometra

In 75 bitches with pyometra single urine samples were examined for gamma-glutamyl transferase (gamma-GT), protein, glucose, specific gravity, bacteria, red blood cells and white blood cells. Serum samples were examined for urea, creatinine, inorganic phosphate and gamma-GT. Biochemical findings were compared with the degree of illness (clinical signs). Twenty one bitches had no signs of renal disease. Seventeen showed only glomerular damage indicated by proteinuria without signs of proximal tubular damage. Thirty seven bitches had increased urinary gamma-GT levels, indicating proximal tubular lesions, which were associated with proteinuria in 35 and renal failure in 16 of them, and worse clinical findings. In all bitches with pyometra serum levels of gamma-GT were comparable to values in control bitches. Glomerular dysfunction seemed to precede proximal tubular lesions, so that gamma-GT-uria in bitches with pyometra was not an early but rather a late indication of a more profound degree of renal dysfunction, that is, proximal tubular renal damage developed after glomerular dysfunction and preceding renal failure.     

Atresia of the nasolacrimal orifice in two thoroughbreds.

Two cases of bilateral atresia of the nasolacrimal orifice are described. The presenting sign was a persistent ocular discharge, clear in the one case and purulent in the other. Treatment by the creation of a fistula between the distal extremity of the blind ending duct and the nasal cavity was successful in both cases.     

Observations on gamma-glutamyl transferase, 5'-nucleotidase and leucine aminopeptidase activities in the plasma of the horse

In 18 horses there was no effect of age or sex on plasma activities of gamma-glutamyl transferase (gamma-GT), 5'-nucleotidase (5'-NT) and leucine aminopeptidase (LAP). All the enzymes were equally stable after storage for one month at -20 degrees C and there was no significant difference between their activities in serum and plasma in clinically normal horses. The pattern of release of gamma-GT, 5'-NT and LAP into plasma was studied in 114 horses which had a variety of orthopaedic, gastrointestinal, cardiovascular and hepatic (necrosis, lipidosis, neoplasia and cirrhosis) conditions. A definitive diagnosis of hepatic disease was established by histological examination of the liver. gamma-GT and 5'-NT were leaked into plasma in hepatic disease and gamma-GT was the more sensitive indicator of liver damage. There was some evidence that gamma-GT and 5'-NT plasma activities may increase in hepatic necrosis as well as in biliary obstruction. LAP was insensitive and not hepatic specific in the horse.     

Transferability of cephalothin to the alveolar cavity in thoroughbreds.

Five Thoroughbreds were classified into 4 groups according to the administration method used for saline solution (saline), ambroxol, and cephalothin sodium (cephalothin). In group A, cephalothin was injected intravenously after oral administration of ambroxol. In group B, cephalothin was injected intravenously after oral administration of saline. Groups C and D were used as control groups. The dose of cephalothin or ambroxol was clinically administrated. Venous blood and bronchoalveolar lavage fluid (BALF) were sampled from each group. In groups A and B, cephalothin concentrations in plasma reached their maximum level 5 min after cephalothin administration and then declined over time. In plasma obtained from groups A and B, there were no significant differences in pharmacokinetic parameters (T1/2, Kel, Vd). By contrast, cephalothin concentrations in BALF reached their peak at 180 min after cephalothin administration in both groups A and B and maintained a relatively high level even after 300 min. These findings indicate that cephalothin requires a relatively long period of time to move from the blood stream to the alveolar cavity, but once transferred to the alveolar cavity, it is preserved for a long time. In groups A and B, cephalothin concentrations in BALF were approximately at the same level. However, in group A, total protein in BALF was lower at 60, 180, and 300 min than the other groups. Then, cephalothin concentration was adjusted to total protein in BALF. After adjustment to total protein in BALF, group A showed a concentration level of cephalothin approximately 1.5-fold higher than that of group B. This suggests that the transferability of cephalothin to the alveolar cavity improves as a result of the oral administration of ambroxol.     

Ileal intussusception in 16 young thoroughbreds.

The paper describes the outcome of 16 cases of short-ileal-ileal intussusception in young Thoroughbred horses. The intussusception was often associated with chronic or intermittent low grade abdominal pain. At laparotomy, only the intussusception was reduced in one horse; in another, a myotomy of the thickened stenosed intussusception was carried out after reduction. In 11 cases as ileocaecal bypass anastomosis was performed proximal to the intussusception after its reduction. One horse was subjected to euthanasia during operation because of irreversible intestinal wall damage and another because of intestinal rupture. One foal had a cardiac arrest following reduction of the intussusception. One horse was subjected to euthanasia 4 months post-operatively because of intractable abdominal pain caused by intestinal adhesions. Although several horses suffered episodes of post-operative abdominal pain, and 2 were subjected to a second laparotomy, 12 horses made an eventual complete recovery.     

Histologic features of the carotid artery trifurcation in thoroughbreds.

The common, external, and internal carotid and occipital arteries were examined histologically at the trifurcation of the common carotid arteries in 13 Thoroughbred foals (0 to 30 days old) and 64 Thoroughbred adults (2 to 4 years old). Calcification in the media of the common carotid and external carotid arteries was observed in 3 of the 13 foals and in 30 of the 64 adult horses. Calcification resembled that seen in M?nckeberg's arteriosclerosis in human beings, the cause of which is unknown.     

Defective gamma-glutamyl carboxylase activity and bleeding in Rambouillet sheep

A flock of Rambouillet sheep was examined because of increased lamb mortality caused by ineffective hemostasis at parturition. Neonatal-affected lambs presented with inadequate hemostasis at the umbilicus, pale mucus membranes, and markedly prolonged activated clotting time. Affected lambs had consistently prolonged 1-stage prothrombin times and activated partial thromboplastin times that supported a defect in the common pathway or defects in both the intrinsic and extrinsic pathway of the coagulation cascade. Decreased activity of vitamin K-dependent procoagulant factors II, VII, IX, and X in male and female lambs suggested either a defect of the hepatic enzyme gamma-glutamyl carboxylase, or vitamin K(1) 2,3 epoxide reductase. Affected lamb hepatic gamma-glutamyl carboxylase activity was markedly decreased compared with that of age- and sex-matched control lambs, while vitamin K(1) 2,3 epoxide reductase and glucose-6-phosphatase activities were similar between an affected and normal lamb. Subcutaneous vitamin K(1) supplementation did not increase vitamin K-dependent procoagulant factor activities in 3 lambs administered vitamin K(1) daily. These data confirm defective gamma-glutamyl carboxylase activity as the cause of impaired coagulation of sheep in this flock. This flock represents the only viable animal model of hereditarily defective gamma-glutamyl carboxylase activity.     

Morphometrical variations of the carpal bones in thoroughbreds and ponies

There is scant morphological data for equine carpal bones despite the frequent pathology in Thoroughbreds (TB). This study aimed to identify morphological and morphometrical variations and similarities in carpal bones between and within TB and Ponies (Po). Carpal bones from nine TB and 13 Po were prepared by boiling and drying. Lateromedial width, dorsopalmar depth, proximodistal height, relative density and volume of each bone were measured. Normalized measurements of the radial (Cr) and third (C3) carpal bones were significantly different in all dimensions, and there were significant variations in relative sizes of articular facets of the ulnar (Cu), C3 and fourth (C4) carpal bones between the groups. Bilaterally, the proportionate volume of the intermediate carpal bone (Ci) was significantly greater in Po while that of Cu and C4 were significantly greater in TB. Relative density of most bones was greater in Po. The palmar tuberosity of the proximal surface of Ci and palmar tubercle on the palmar surface of Cu were more prominent and relatively larger in TB. In the second carpal bone (C2), the distal extent of the proximal articular surface on the palmar surface was greater in Po. The inconsistent first carpal bone (C1) was relatively larger in Po. Morphometrical similarities and differences in carpal bones between TB and Po indicate potential effects of selection for body size or fast exercise.     

Urinary gamma-glutamyl transpeptidase activity in dogs with gentamicin-induced nephrotoxicity

Serum creatinine concentrations, 24-hour endogenous creatinine clearance, and 24-hour urinary gamma-glutamyl transpeptidase (UGGT) activity were measured daily in 6 dogs given nephrotoxic dosages of gentamicin (10 mg/kg of body weight) every 8 hours for 10 days. Mean UGGT activity was significantly increased by day 5 (P less than 0.05) and preceded significant increases in serum creatinine values (greater than 2.0 mg/dl) observed on day 9. Endogenous creatinine clearance remained within normal limits (2.98 +/- 0.96 ml/min/kg) until day 8. Urinalyses performed 8 days after initiation of gentamicin treatment indicated renal tubular damage (granular casts) in 1 of the 6 dogs, and glucosuria in 3 of the 6 dogs. Measurement of UGGT activity was a more sensitive and reliable method of assessing acute renal tubular damage induced by gentamicin than were serum creatinine concentrations or 24-hour endogenous creatinine clearance.     

Ultrasonic measurement of arterial blood pressure in conditioned thoroughbreds.

Indirect systolic and diastolic arterial pressure measurements of 456 Thoroughbred horses of various ages and sex stabled at 9 different race tracks were measured with an ultrasonic-Doppler device interfaced with a sphygmomanometer cuff. The mean systolic pressure was 111.8 +/- 13.3 mmHg and the mean diastolic pressure was 69.6 +/- 13.8 mmHg in this population.     

Ultrasound speed in the metacarpal cortex--a survey of 347 thoroughbreds in training.

Transmission ultrasound speed was determined in the third metacarpal bone of 347 Thoroughbred racehorses in training. In addition to direct measurement of apparent ultrasound speed and lateral bone diameter, several derived parameters were estimated (cortical ultrasound speed, corticomedullary ratio and cortical cross-sectional area). Multiple regression equations were developed for each ultrasound measurement using the explanatory variables: sex, age, duration and intensity of training, preparation number and previous shin soreness. The horses (114 females, 82 entire males and 151 geldings ranging in age from 20 to 116 months) had been in continuous training for an average of 10.0 weeks when measurements were made. All measurements except corticomedullary ratio were influenced by the sex of the horse. Geldings had significantly lower ultrasound transmission speed than entire males and females, reflecting a lower bone density. However, the geldings had larger cross-sectional areas (ie bone size). We suggest that the relationship between low ultrasound speed (ie low bone density) and large cross-sectional area maintains the overall mechanical integrity of the metacarpus. This relationship (high ultrasound speed and low cross-sectional area) was also found in each sex group. Ultrasound speed and corticomedullary ratio, but not cross-sectional area, were affected by age. Both duration and intensity of training influenced the ultrasound speed measurements. This study indicated that sex, age and state of training affect ultrasound results, but this explained only about 30% of the variance in the data. Other factors, ie genetic variation in bone density and size, differences in soft tissue thickness and distal limb temperature, presumably account for most of the variance.