Canine pancreatic-specific lipase concentrations in clinically healthy dogs and dogs with naturally occurring hyperadrenocorticism.

BACKGROUND: Specificity of canine pancreatic lipase immunoreactivity (cPLI) assays in dogs with hyperadrenocorticism (HAC) is unknown. HYPOTHESIS: Results of cPLI assays differ for clinically healthy dogs and dogs with HAC. ANIMALS: Seventeen healthy dogs and 20 dogs with HAC diagnosed by ACTH stimulation test results without evidence of clinical pancreatitis. METHODS: Dogs were enrolled between December 2009 and November 2010. Serum cPLI concentrations were determined by quantitative (Spec cPL test, SPEC) and semiquantitative (SNAP cPL test, SNAP) assays. Results were categorized as normal, equivocal, or abnormal (SPEC) or negative or positive (SNAP). Associations between group and cPLI were assessed using Fisher's exact test or the Mann-Whitney U-test. Spearman rank correlation coefficients (ρ) were determined for SNAP and SPEC results. Significance was set at P < .05. RESULTS: Spec cPL test concentrations were significantly (P < .001) higher in dogs with HAC (491.1 µg/L) than in healthy dogs (75.2 µg/L), with more abnormal SPEC results in HAC dogs (P < .001). There were more (P = .002) positive SNAP results in dogs with HAC (55%) than in healthy dogs (6%). SNAP and SPEC results were highly correlated (ρ = 0.85; P < .001). CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with HAC had higher SPEC concentrations and more positive SNAP results than clinically healthy dogs with normal ACTH stimulation test results. Specificity of SPEC and SNAP assays in HAC dogs without clinical pancreatitis were 65 and 45%, respectively. Pending further study, SNAP and SPEC results should be interpreted cautiously in dogs with HAC to avoid false diagnosis of concurrent pancreatitis.

Effect of serum storage, anti-inflammatory oral doses of prednisone, and spontaneous hyperadrenocorticism on serum glutamate dehydrogenase activity in dogs.

BACKGROUND: Glutamate dehydrogenase (GLDH) is a mitochondrial enzyme with highest activity in periacinar hepatocytes. It is reported to be a sensitive indicator of hepatic injury; however, results of studies regarding tissue specificity are contradictory. OBJECTIVES: The purpose of the study reported here was to examine the effect of 3 factors on serum GLDH activity in dogs: serum storage, anti-inflammatory oral doses of prednisone, and spontaneous hyperadrenocorticism (HAC). METHODS: Stability of enzyme activity was determined by comparing serum samples stored at approximately 20 degrees C, 4 degrees C, and 20 degrees C for 4, 24, 48, and 72 hours, 1 week, and 6 months. To determine whether orally administered prednisone affected GLDH activity, the median difference in serum GLDH activity was compared between 5 untreated control dogs and 8 dogs that had received a tapering oral dose of prednisone. Lastly, GLDH enzyme activity was compared between 17 dogs with HAC and 16 age-matched controls. RESULTS: GLDH activity remained stable for 48 hours, 1 week, and 6 months, in serum stored at approximately 20 degrees C, 4 degrees C, and 20 degrees C, respectively. The median change in GLDH activity was not significantly different between dogs receiving prednisone and controls; however, dogs with HAC had significantly higher values than those of age-matched controls. CONCLUSIONS: Serum samples should be maintained at 4 degrees C if analysis of GLDH activity will be delayed by >48 hours; serum stored at 20 degrees C yields reliable results for up to 6 months. Serum GLDH activity was not increased in most dogs receiving short-term, anti-inflammatory oral doses of prednisone, in contrast to its increased activity in dogs with HAC.

Adrenal GRK2 upregulation mediates sympathetic overdrive in heart failure.

Cardiac overstimulation by the sympathetic nervous system (SNS) is a salient characteristic of heart failure, reflected by elevated circulating levels of catecholamines. The success of beta-adrenergic receptor (betaAR) antagonists in heart failure argues for SNS hyperactivity being pathogenic; however, sympatholytic agents targeting alpha2AR-mediated catecholamine inhibition have been unsuccessful. By investigating adrenal adrenergic receptor signaling in heart failure models, we found molecular mechanisms to explain the failure of sympatholytic agents and discovered a new strategy to lower SNS activity. During heart failure, there is substantial alpha2AR dysregulation in the adrenal gland, triggered by increased expression and activity of G protein-coupled receptor kinase 2 (GRK2). Adrenal gland-specific GRK2 inhibition reversed alpha2AR dysregulation in heart failure, resulting in lowered plasma catecholamine levels, improved cardiac betaAR signaling and function, and increased sympatholytic efficacy of a alpha2AR agonist. This is the first demonstration, to our knowledge, of a molecular mechanism for SNS hyperactivity in heart failure, and our study identifies adrenal GRK2 activity as a new sympatholytic target.

Adrenal hyperplasia and adenomas are associated with inhibition of phosphodiesterase 11A in carriers of PDE11A sequence variants that are frequent in the population.

Several types of adrenocortical tumors that lead to Cushing syndrome may be caused by aberrant cyclic AMP (cAMP) signaling. We recently identified patients with micronodular adrenocortical hyperplasia who were carriers of inactivating mutations in the 2q-located phosphodiesterase 11A (PDE11A) gene. We now studied the frequency of two missense substitutions, R804H and R867G, in conserved regions of the enzyme in several sets of normal controls, including 745 individuals enrolled in a longitudinal cohort study, the New York Cancer Project. In the latter, we also screened for the presence of the previously identified PDE11A nonsense mutations. R804H and R867G were frequent among patients with adrenocortical tumors; although statistical significance was not reached, these variants affected significantly enzymatic function in vitro with variable increases in cAMP and/or cyclic guanosine 3',5'-monophosphate levels in HeLa and HEK293 cells. Adrenocortical tissues carrying the R804H mutation showed 2q allelic losses and higher cyclic nucleotide levels and cAMP-responsive element binding protein phosphorylation. We conclude that missense mutations of the PDE11A gene that affect enzymatic activity in vitro are present in the general population; protein-truncating PDE11A mutations may also contribute to a predisposition to other tumors, in addition to their association with adrenocortical hyperplasia. We speculate that PDE11A genetic defects may be associated with adrenal pathology in a wider than previously suspected clinical spectrum that includes asymptomatic individuals.

Serum alkaline phosphatase activity in Scottish Terriers versus dogs of other breeds.

OBJECTIVE: To determine whether Scottish Terriers have higher serum alkaline phosphatase (ALP) activities and a higher prevalence of diseases commonly associated with high serum ALP activity than do dogs of other breeds. DESIGN: Retrospective case-control study. ANIMALS: 85 Scottish Terriers and 340 age-matched control dogs that were not Scottish Terriers. PROCEDURE: Medical records were reviewed, and data for year of evaluation, age, sex, breed, serum ALP activity, and final diagnosis were recorded. RESULTS: Scottish Terriers had a significantly higher mean serum ALP activity than did control dogs (1,520 U/L vs 306 U/L). Regardless of breed, dogs that had a disease commonly associated with high serum ALP activity had a significantly higher mean serum ALP activity than did dogs without such diseases (1,304 U/L vs 427 U/L). Scottish Terriers were 2.4 times as likely to have a disease commonly associated with high serum ALP activity than were control dogs, but Scottish Terriers with diseases commonly associated with high serum ALP activity had a significantly higher mean ALP activity than did control dogs with such diseases (2,073 U/L vs 909 U/L), and Scottish Terriers without such diseases had a significantly higher mean serum ALP activity than did control dogs without such diseases (1,349 U/L vs 228 U/L). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that Scottish Terriers have higher serum ALP activities than do dogs of other breeds. Although Scottish Terriers also have a higher prevalence of diseases associated with high serum ALP activity, this alone did not explain the higher mean serum ALP activity in the breed.

Na(+), K(+)-ATPase content in skeletal muscle of dogs with pituitary-dependent hyperadrenocorticism.

Several hormones regulate Na(+), K(+)-ATPase content in the muscle cell membrane, which is essential for maintaining muscle cell excitability. Chronic glucocorticoid excess is associated with muscle weakness and reduced endurance. We hypothesized that chronic glucocorticoid excess affects Na(+), K(+)-ATPase content in canine skeletal muscle, and contributes to reduced endurance and muscle weakness associated with pituitary-dependent hyperadrenocorticism (PDH) in dogs. Therefore, Na(+), K(+)-ATPase content in skeletal muscle was evaluated before and after hypophysectomy and hormone replacement (cortisone and l-thyroxin) in dogs with PDH (n=13), and in healthy controls (n=6). In addition, baseline and exercise-induced changes in plasma electrolyte concentrations and acid-base balance were evaluated before and after hypophysectomy in dogs with PDH. Na(+), K(+)-ATPase content of gluteal muscle in dogs with PDH was significantly lower than in control dogs (201+/-13pmol/g versus 260+/-8pmol/g wet weight; P<0.01). Similar differences were found in palatine muscle. After hypophysectomy and on hormone replacement, Na(+), K(+)-ATPase was increased (234+/-7pmol/g wet weight). Both plasma pH and base excess in dogs with PDH (7.44+/-0.01; 1.7+/-0.6mmol/l, respectively) were significantly higher (P<0.05) than after hypophysectomy and hormone replacement (7.41+/-0.01; -0.2+/-0.4mmol/l, respectively). Exercise induced respiratory alkalosis, but did not result in hyperkalemia in dogs with PDH. In conclusion, chronic glucocorticoid excess in dogs with PDH is associated with decreased Na(+), K(+)-ATPase content in skeletal muscle. This may contribute to reduce endurance in canine PDH, although dogs with PDH did not exhibit exercise-induced hyperkalemia. Na(+), K(+)-ATPase content normalized to values statistically not different from healthy controls after hypophysectomy and hormone replacement.

The use of trilostane for the treatment of alopecia X in Alaskan malamutes.

Three Alaskan malamutes with hair loss and slightly elevated blood concentrations of 17-hydroxyprogesterone after stimulation with adrenocorticotropic hormone (ACTH) were treated with trilostane. Trilostane, an inhibitor of 3 beta-hydroxysteroid dehydrogenase, was given twice daily at a dose of 3.0 to 3.6 mg/kg per day orally for 4 to 6 months. Routine ACTH stimulation tests were performed over 8 months to evaluate the degree of adrenal function suppression. Treatment with trilostane led to complete hair regrowth in all three dogs within 6 months. No adverse effects associated with trilostane were recognized.

Serum lactate dehydrogenase activity increases in both endogenous and exogenous hypercorticisms.

Both endogenous and exogenous hypercorticisms are associated with a modest increase of the activity of serum lactate dehydrogenase. Considering both the wide use of this parameter and the frequent prescription of corticosteroids in clinical practice, awareness of this phenomenon is useful to avoid unnecessary investigations.

Lack of an ovarian function influence on the increased adrenal androgen secretion present in women with functional ovarian hyperandrogenism.

OBJECTIVE: To evaluate whether ovarian function might have an influence on the adrenal hyperandrogenism present in patients with functional ovarian hyperandrogenism. DESIGN: Controlled clinical study. SETTING: Tertiary institutional hospital. PATIENT(S): Twenty-nine hirsute women with functional ovarian hyperandrogenism and 12 normal controls. INTERVENTION(S): The ACTH and GnRH tests were performed before and during triptorelin-induced ovarian suppression in patients. The normal women served as controls for the ACTH test. MAIN OUTCOME MEASURE(S): Basal and ACTH-stimulated steroid values. RESULT(S): All patients presented elevated T and free androgen index, which normalized after triptorelin. Patients with functional ovarian hyperandrogenism and adrenal hyperandrogenism, defined by elevated basal DHEAS (n = 10), presented enhanced delta 4-17, 20-lyase activity, which persisted during ovarian suppression. delta 4-17,20-lyase activity was normal in the functional ovarian hyperandrogenism patients without adrenal hyperandrogenism (n = 19). No correlation was observed between the any of the indexes of the adrenal enzymatic activities evaluated and plasma E2 or T. CONCLUSION(S): Increased adrenal delta 4-17,20-lyase activity is present in functional ovarian hyperandrogenism women with adrenal hyperandrogenism. No influence of the excess ovarian androgens or estrogens was found on any of the adrenal enzymatic pathways explored.

Apparent cortisone reductase deficiency: a unique form of hypercortisolism.

We describe two female siblings who had production of cortisol (F; as determined from excretion of urinary metabolites) high enough to give rise to Cushing's disease, but who had no clinical indications of the condition. The teenage patients were hirsute as a result of adrenal hyperandrogenism. A notable feature of the condition was the elevated excretion of corticosteroid metabolites with 11-carbonyl groups and very low excretion of 11 beta-hydroxylated steroids. We termed this disorder apparent cortisone (E) reductase disorder. The steroid metabolite phenotype appeared to be the opposite of that seen in the apparent mineralocorticoid excess syndrome, in which the excretion of 11-keto compounds is attenuated. As an example, the tetrahydrocortisol plus 5 alpha-tetrahydrocortisol/tetrahydrocortisone ratio was about 0.04 compared to normal values of about 1.0 and apparent mineralocorticoid excess syndrome values of 5.0-50.0. Paradoxically, among the F metabolites that had not undergone A-ring reduction, 11 beta-hydroxylated steroids dominated over 11-carbonyl compounds. The F/E ratio was about 1.8 compared to an average normal value of 0.54. Neither the father nor the mother of the patient had abnormal F metabolite/E metabolite ratios, although the father did excrete highly elevated free E and F, possibly an unrelated condition. A conclusion was not reached regarding the basis of the disorder. We considered that the most likely causes were 1) defective hepatic 11 beta-hydroxysteroid dehydrogenase-1, 2) failure to develop the adult form of F metabolism, or 3) excessive activity of A ring reduction enzymes acting on E.

[Effect of vibration on gamma-aminobutyric acid metabolism in the brain in various functional conditions of the adrenal cortex]. / Vliianie vibratsii na obmen gamma-aminomaslianoi kisloty mozga pri razlichnykh funktsional'nykh sostoianiiakh kory nadpochechnikov.

The low-frequency vibration during 30 min (20 Hz, A = 0.4 mm) has been studied for its influence on the level of components of the GABA system and dicarbonic ++amino acids in male rats at hypo- and hyperfunction of the adrenal cortex. It is shown that under these conditions of the experiment the GABA level and glutamate-decarboxylase activity increase. Hyperfunction of the adrenal cortex against the background of vibration causes a relatively less pronounced increase in the GABA content, than the vibration alone or against the background of inhibition of adrenocortical function in the organism.

Fertility in women with late-onset adrenal hyperplasia due to 21-hydroxylase deficiency.

Fertility was evaluated in 53 female patients with late-onset adrenal hyperplasia (LAH) due to 21-hydroxylase deficiency. The majority of patients (n = 33) were seen for isolated postpubertal hirsutism, 9 patients consulted for sterility, and 11 for irregular menstrual cycles. At the time of diagnosis, the ages of patients ranged from 15-40 yr (mean +/- SD, 24.6 +/- 5.2). No patient had major signs of virilization. The plasma 17-hydroxyprogesterone level was higher than normal in all patients (26.8 +/- 18.9 nmol/L; range, 3.4-139.4) and dramatically increased to 140.1 +/- 80.6 nmol/L (range, 35.2-324.2) after ACTH treatment. Plasma androgen levels were high (testosterone, 3.25 +/- 2.03 nmol/L; delta 4-androstenedione, 13.65 +/- 5.60 nmol/L). Plasma basal and LHRH-stimulated values were normal for FSH and high for LH. Basal and TRH-stimulated plasma PRL levels were normal. Among these 53 LAH patients, only 20 desired a pregnancy. These had a total of 38 pregnancies. Ten patients became pregnant before the diagnosis of LAH and without any treatment; they had a total of 18 pregnancies, 12 of which were successful. Moreover, 19 normal pregnancies without any spontaneous abortion were carried to term by 14 of 16 hydrocortisone-treated patients. One patient needed the association of one cure of clomiphene citrate. Hypofertility in LAH patients seems, therefore, to be relative. Its mechanism is hormonal, with anovulation or dysovulation, due to the continuous steroid feedback of adrenal origin on the hypothalamo-pituitary axis. Hydrocortisone is the appropriate treatment in most cases, reducing adrenal androgen overproduction and relieving hypothalamic-pituitary gonadotropin function, thereby making possible cyclic ovarian activity and ovulations.

Corticosteroid-induced alkaline phosphatase isoenzyme in the diagnosis of canine hypercorticism.

Corticosteroid-induced isoenzyme of alkaline phosphatase (AP) can easily be demonstrated in canine plasma as a routine procedure because of its greater heat stability at 65 degrees C in comparison with that of other AP-isoenzymes. In this study the accuracy of this test for the diagnosis of hypercorticism was investigated. The AP-65 degrees C test had its highest efficiency when applied to plasma AP levels exceeding 150 units/litre. In a group of 146 dogs, clinically suspected of having hyperadrenocorticism, the test had a sensitivity of 0.92 and a positive predictive value for a positive test result of 0.89. Its lack of specificity (0.44) makes it unsuitable as a diagnostic test. The main application of AP-65 degrees C is in detecting hypercorticism in dogs by routine laboratory measurements, as was demonstrated in 711 dogs, in which a positive predictive value for the presence of hypercorticism of 0.89 was found.

[Immunoreactive trypsin in the blood serum of patients with endogenous hypercorticism]. / Immunoreaktivnyi tripsin syvorotki krovi u bo'lnykh s endo- gennym giperkortitsizmom.

Basal immunoreactive serum trypsin (RIT) was determined in comparative study of 46 patients with adrenocortical hyperfunction and 24 patients with hypocorticism for specifying the potentialities of the diagnostic test. Excess of endogenous corticosteroids is accompanied by a marked increase in the RIT serum concentration, this increase is particularly pronounced in Itsenko-Cushing syndrome and in exacerbations of Itsenko-Cushing disease in comparison with its level in Itsenko-Cushing disease remission. The presence of steroid diabetes had no significant RIT changes in Itsenko-Cushing disease. Attendant chronic pancreatitis that developed in patients with adrenocortical hyperfunction had no influence on blood serum RIT content. In patients with adrenal steroid deficiency who did not take glucocorticoids the serum RIT concentration was lower than that in those who constantly used hormones. RIT is increased in cases of chronic pancreatitis combined with chronic adrenal insufficiency. Measurement of the basal serum RIT may contribute to the diagnosis of pancreatitis in patients with hypocorticism but provides no information on this pathology in patients with endogenous hypercorticism.

Polycystic ovarian disease and congenital and late-onset adrenal hyperplasia.

This article surveys the congenital and late-onset forms of the common steroidogenic enzyme defects of the adrenal cortex--steroid 21-hydroxylase, steroid 11 beta-hydroxylase, and 3 beta-hydroxysteroid dehydrogenase deficiencies--in connection with the occurrence of polycystic ovarian disease.

Amniotic fluid levels of 17 alpha-hydroxyprogesterone during human pregnancy: pre-natal diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

Levels of 17 alpha-hydroxyprogesterone were estimated by radioimmunoassay in 174 amniotic fluid specimens obtained from 162 normal pregnancies of 16-20 weeks gestation. Another 18 specimens from 11 normal pregnancies between 25-42 weeks gestation and 7 specimens from 7 women who each previously had given birth to a child affected with CAH were also studied. There was no sex difference in AF 17 alpha-OH-progesterone levels, nor any significant downward trend in concentrations throughout the observed gestation period. Among the 7 subjects with previous history of CAH offsprings, 4 demonstrated normal levels of AF 17 alpha-OH-progesterone and 3 significantly higher values. HLA-typing of the cultivated amniotic cells confirmed these 4 cases to be heterozygous for 21-hydroxylase deficiency. The three subjects with high AF 17 alpha-OH-progesterone levels delivered babies affected with CAH, although HLA-typing in one case was non-conclusive. The failure of HLA-typing in 1 case for a confirmatory diagnosis indicates that the prenatal diagnosis of CAH must continue to rest on joint endocrinological and genetical investigations.

Dynamics of adrenal steroidogenesis in childhood: changes in the excretion of 16-oxygenated- and 11-oxygenated-steroids by 21-hydroxylase deficient children at various ages.

The close relationship between C19O2 steroid excretion and the ratio of C19O2/C21O5 steroids indicates that it is the elevation of C17,20-lyase activity, which represents the decisive factor in the cessation of androgen-corticoid disproportion during the puberty of healthy children. In 3-6 year-old C21-hydroxylase deficient children treated with corticoids in doses only partially suppressing endogenous ACTH secretion, the excretion of total C19 steroids increased continuously parallel with a well defined elevation of 16 alpha-oxygenated-C21 steroid excretion. The patients did not show the physical signs of adrenarche before six years. This can be attributed to three factors: a) substitutional corticoid therapy; b) intraglandular control of delta 5-pathway by 16 alpha-hydroxylation of C21 steroids; c) neutralisation by 11 beta-hydroxylation of the androgen effect of C19O2 steroids.

[Adrenal hyperandrogenism due to enzyme disturbance of late onset (author's transl)]. / Hyperandrogénies surrénaliennes par trouble enzymatique à révélation tardive chez la femme.

In the context of hyperandrogenism, the group of hyperandrogenism due to disturbances in hormon-synthesis of late onset is worthy of being considered separately, not by virtue of its prevalence but by the fact that its course may be one of isolate hirsutism (3 cases out of 11 in this study), or even sterility. The diagnosis may be of varying difficulty, because of the incomplete nature of the block. Eleven cases are reported, ten due to a partial deficit in 21 hydroxydation, and one due to a deficit in 11 hydroxydation. The presence of cortisone precursors is often more significant in stimulation tests. Estimation of blood testosterone levels may give somewhat high results in certain cases, but it must be emphasized that it may be diminished dexamethasone and the estimateion of delta 4 androstenedione is of value. In difficult cases, the diagnosis of a minor or incomplete disturbance is based upon a combination of biological, statistical and dynamic arguments. However this diagnosis is important since cortisone at low inhibitory doses are effective, in particular against menstrual disorders, sometimes making it possible to rapidly correct sterility.