Evolution of blood donation patterns in a hospital-based blood centre over a seven-year period: implications for donor recruitment and retention.

OBJECTIVE: The aim of this study is to investigate the effect of a public appeal to encourage voluntary blood donation by comparing the pattern of blood donations in 2000 and 2007. METHODS: A retrospective analysis of blood donation records was conducted at the University Hospital of the West Indies (UHWI) Blood Collection Centre from April to December of 2000 and 2007. Data were analysed to identify any significant changes in donation patterns and donor profiles. RESULTS: The total number of blood donor records reviewed was 3194 in 2000 and 2634 in 2007 representing 69.0% and 72.3% of the total blood donations, respectively. Autologous donations accounted for 1% in 2000 and 2.2% in 2007; however, there was no corresponding change in voluntary donations (3.4% in 2000 and 3.2% in 2007). Despite a reduction in the number of first-time donors (1539 in 2000 and 1115 in 2007), the percentage of units discarded for the presence of a marker of transfusion transmission infection (TTI) increased, being 6.5% in 2000 and 7.4% in 2007. Human T-lymphotropic virus (HTLV) was the most common infectious marker in 2000 (3.4% of donors) whereas reactive Venereal Disease Research Laboratory (VDRL) predominated in 2007 (3.6% of donors). CONCLUSION: The per capita donations (0.99% in 2000 and 0.88% in 2007) failed to meet the World Health Organization (WHO) recommendation for an adequate blood supply of 1-3%. Despite a national effort to improve voluntary donations, the positive changes in the pattern of blood donation over a period of seven years were limited to a decrease in the proportion of first-time donors and an increase in blood donors with one to four previous donations.

Prevalence of the metabolic syndrome in patients presenting to the University Hospital of the West Indies: a need to adopt proactive screening and specific management policy / Prevalencia del síndrome metabólico en pacientes que acuden al Hospital Universitario de West Indies: necesidad de adoptar un tamizaje proactivo y políticas de tratamiento específico

Studies have shown that the metabolic syndrome (MetS), a major risk factor for the development of Type 2 diabetes mellitus and cardiovascular disease, is higher among psychiatric patients on antipsychotic medications than the general population. While studies on the prevalence of MetS in the Jamaican adult population have been undertaken, no such study has been done on the corresponding psychiatric population. The purpose of this study was to determine the prevalence of MetS in a Jamaican adult psychiatric inpatient population. The study group comprised thirty-eight patients with a primary DSM-IV-TR Axis 1 diagnosis. Criteria for the diagnosis of MetS were the presence of any three or more of five factors as defined by using the International Diabetes Federation (IDF) and American Heart Association/National Heart Lung and Blood Institute (AHA/NHLBI) consensus agreement. The prevalence of MetS in this cohort was 28.9% and was associated with significantly higher abdominal obesity (p = 0.010), elevated blood pressure (p = 0.000), elevated triglycerides (p = 0.019) and low high density lipoprotein-cholesterol (p = 0.016) when compared with patients not diagnosed with MetS. Metabolic syndrome was common in this group of psychiatric patients and likely represents a pathway to the future development of Type 2 diabetes mellitus and cardiovascular disease. Screening and continuous monitoring will allow for early intervention and possibly prevention of increased morbidity and mortality in this vulnerable population.

Los estudios han mostrado que el síndrome metabólico (SMet) - un factor de riesgo mayor para el desarrollo de la diabetes mellitus tipo 2 y la enfermedad cardiovascular - es más alto entre los pacientes psiquiátricos bajo medicamentos antipsicóticos que entre la población general. Si bien se han llevado a cabo estudios sobre la prevalencia del SMet en la población adulta jamaicana, no se han realizado estudios de esta clase en la población psiquiátrica correspondiente. El propósito de este estudio fue determinar la prevalencia del SMet en una población jamaicana adulta de pacientes hospitalizados. El grupo de estudio comprendió treinta y ocho pacientes con diagnóstico primario DSM-IV-TR de eje I. Los criterios para el diagnóstico de SMet se basaron en la presencia de tres o más de cinco factores, los cuales fueron definidos usando el acuerdo por consenso de la Federación Internacional de la Diabetes (FID) y la Asociación Nacional de Cardiología/Instituto Nacional del Corazón, el Pulmón y la Sangre (AHA/NHLBI). La prevalencia de SMet en esta cohorte fue 28.9%, y se hallaba asociada con obesidad abdominal significativamente más alta (p = 0.010), presión sanguínea elevada (p = 0.000), triglicéridos elevados (p = 0.019), y bajos niveles de colesterol-lipoproteína de alta densidad (p = 0.016), al compararse con pacientes no diagnosticados con SMet. El síndrome metabólico fue común en este grupo de pacientes psiquiátricos y probablemente representa una vía al desarrollo futuro de la diabetes mellitus tipo 2 y la enfermedad cardiovascular. El tamizaje así como el monitoreo continuos permitirán la intervención temprana y la posible prevención del aumento de la morbosidad y la mortalidad en esta población vulnerable.

Prevalence of the metabolic syndrome in patients presenting to the university hospital of the West Indies: a need to adopt proactive screening and specific management policy.

Studies have shown that the metabolic syndrome (MetS), a major risk factor for the development of Type 2 diabetes mellitus and cardiovascular disease, is higher among psychiatric patients on antipsychotic medications than the general population. While studies on the prevalence of MetS in the Jamaican adult population have been undertaken, no such study has been done on the corresponding psychiatric population. The purpose of this study was to determine the prevalence of MetS in a Jamaican adult psychiatric inpatient population. The study group comprised thirty-eight patients with a primary DSM-IV-TR Axis 1 diagnosis. Criteria for the diagnosis of MetS were the presence of any three or more of five factors as defined by using the International Diabetes Federation (IDF) and American Heart Association/National Heart Lung and Blood Institute (AHA/NHLBI) consensus agreement. The prevalence of MetS in this cohort was 28.9% and was associated with significantly higher abdominal obesity (p = 0.010), elevated blood pressure (p = 0.000), elevated triglycerides (p = 0.019) and low high density lipoprotein-cholesterol (p = 0.016) when compared with patients not diagnosed with MetS. Metabolic syndrome was common in this group of psychiatric patients and likely represents a pathway to the future development of Type 2 diabetes mellitus and cardiovascular disease. Screening and continuous monitoring will allow for early intervention and possibly prevention of increased morbidity and mortality in this vulnerable population.

The predictive value of urinary vanillylmandelic acid testing in the diagnosis of phaeochromocytoma at the University Hospital of the West Indies.

OBJECTIVE: To investigate the positive predictive value (PPV) of urinary vanillylmandelic acid (VMA) testing in the diagnosis of phaeochromocytoma and to describe the features associated with phaeochromocytoma at the University Hospital of the West Indies (UHWI). SUBJECTS AND METHODS: There were 551 VMA tests performed from January 2003 to June 2009 and 122 tests in 85 patients were elevated (ie > or = 35 micromol/24 hr). The study patients were categorized as: (i) 'surgical' (5 patients who underwent surgery) or (ii) 'non-surgical' (remaining 80 patients). Forty medical charts (out of 85) were reviewed using a standardized data extraction form. RESULTS: The median age for patients in the non-surgical group (with charts reviewed, n = 35) was 36 years (range 9-70) and the median VMA was 43 micromol/24 hr (IQR 38-51). Of these patients, 83% had one or no symptom typical of phaeochromocytoma. In the surgical group the median VMA was 58 micromol/24 hr (IQR 44-101); phaeochromocytoma was confirmed histologically in 3 patients, all of whom had several symptoms typical of catecholamine excess. VMA testing had a PPV of 8%, specificity of 79% and sensitivity of 100%. CONCLUSIONS: VMA testing at UHWI has poor specificity and high sensitivity. These results contrast with international data showing that VMA testing is poorly sensitive but highly specific. The use of assays with higher specificity (eg plasma or urinary metanephrines) may represent a more cost-effective approach to biochemical screening at UHWI.

Improvement in HDL cholesterol in postmenopausal women supplemented with pumpkin seed oil: pilot study.

OBJECTIVE: Pumpkin seed oil is rich in phytoestrogens and animal studies suggest that there is some benefit to supplementation in low estrogen conditions. This study is the first to evaluate the benefit of pumpkin seed oil in postmenopausal women. METHODS: This pilot study was randomized, double-blinded and placebo-controlled. Study participants included 35 women who had undergone natural menopause or had iatrogenically entered the climacteric due to surgery for benign pathology. Wheat germ oil (placebo; n = 14) and pumpkin seed oil (n = 21) were administered to eligible participants over a 12-week period at a dose of 2 g per day. Serum lipids, fasting plasma glucose and blood pressure were measured and an 18-point questionnaire regarding menopausal symptoms was administered; the atherogenic index was also calculated. Differences between groups, as well as before and after the period of supplementation, were evaluated with Student's t-test, Wilcoxon matched-pair signed-ranked test and Mann-Whitney test, as appropriate (Stata version 10.1). RESULTS: Women receiving pumpkin seed oil showed a significant increase in high density lipoprotein cholesterol concentrations (0.92 ± 0.23 mmol/l vs. 1.07 ± 0.27 mmol/l; p = 0.029) and decrease in diastolic blood pressure (81.1 ± 7.94 mmHg vs. 75.67 ± 11.93 mmHg; p < 0.046). There was also a significant improvement in the menopausal symptom scores (18.1 ± 9.0 vs. 13.2 ± 6.7; p < 0.030), with a decrease in severity of hot flushes, less headaches and less joint pains being the main contributors. Women in the group receiving wheat germ oil reported being more depressed and having more unloved feeling. CONCLUSION: This pilot study showed pumpkin seed oil had some benefits for postmenopausal women and provided strong evidence to support further studies.

The predictive value of urinary vanillylmandelic acid testing in the diagnosis of phaeochromocytoma at the University Hospital of the West Indies / El valor predictivo de la prueba del ácido vanilmandélico en orina para el diagnóstico de la feocromositoma en el Hospital Universitario de West Indies

OBJECTIVE: To investigate the positive predictive value (PPV) of urinary vanillylmandelic acid (VMA) testing in the diagnosis of phaeochromocytoma and to describe the features associated with phaeo chromocytoma at the University Hospital of the West Indies (UHWI). SUBJECTS AND METHODS: There were 551 VMA tests performed from January 2003 to June 2009 and 122 tests in 85 patients were elevated (ie > 35 µmol/24 hr). The study patients were categorized as: (i) 'surgical' (5 patients who underwent surgery) or (ii) 'non-surgical' (remaining 80 patients). Forty medical charts (out of 85) were reviewed using a standardized data extraction form. RESULTS: The median age for patients in the non-surgical group (with charts reviewed, n = 35) was 36 years (range 9-70) and the median VMA was 43 µmol/24 hr (IQR 38-51). Of these patients, 83% had one or no symptom typical of phaeochromocytoma. In the surgical group the median VMA was 58 µmol/24 hr (IQR 44-101); phaeochromocytoma was confirmed histologically in 3 patients, all of whom had several symptoms typical of catecholamine excess. VMA testing had a PPV of 8%, specificity of 79% and sensitivity of 100%. CONCLUSIONS: VMA testing at UHWI has poor specificity and high sensitivity. These results contrast with international data showing that VMA testing is poorly sensitive but highly specific. The use of assays with higher specificity (egplasma or urinary metanephrines) may represent a more cost-effective approach to biochemical screening at UHWI.

OBJETIVO: Investigar el valor predictivo positivo (VPP) de las pruebas del ácido vanilmandélico urinario (VMA) en el diagnóstico de la feocromositoma y describir las características asociadas con la feocromositoma en el Hospital de la Universidad de West Indies (HUWI). SUJETOS Y MÉTODOS: Se realizaron unas 551 pruebas de VMA de enero de 2003 a junio de 2009, y 122 de las pruebas en 85 pacientes tuvieron resultados elevados (ie > 35 µmol/24 hr). Los pacientes del estudio fueron clasificados como: (i) "quirúrgicos" (5 pacientes que se sometieron a cirugía) ó (ii) "no quirúrgicos" (los 80 pacientes restantes). Se revisaron cuarenta historias clínicas (de 85) mediante un formulario estandarizado de extracción de datos. RESULTADOS: El promedio de edad de los pacientes en el grupo no quirúrgico (con historias clínicas, n = 35) fue de 36 años (rango 9-70) y la mediana VMA fue 43 µmol/24 h (IQR 38-51). De estos pacientes, 83% tenían uno o ningún síntoma típico de la feocromositoma. En el grupo quirúrgico la mediana VMA fue 58 µmol/24 h (IQR 44-101). La feocromositoma fue confirmada histológicamente en 3 pacientes, cada uno de los cuales presentó síntomas típicos de exceso de catecolaminas. Las pruebas de VMA tuvieron un VPP de 8%, una especificidad de 79%, y una sensibilidad de 100%. CONCLUSIONES: Las pruebas de VMA en HUWI poseen pobre especificidad y alta sensibilidad. Estos resultados contrastan con los datos internacionales que muestran que la prueba de VMA es pobremente sensible pero altamente específica. El uso de ensayos con mayor especificidad (por ejemplo, metanefrinas plasmáticas o urinarias) puede representar un método costo-efectivo a la hora de realizar el pesquisaje bioquímico en HUWI.

Serum creatine kinase and lactate dehydrogenase activities in patients with thyroid disorders.

BACKGROUND AND OBJECTIVES: There is the recognition of a pattern of elevations of serum enzymes in hyperthyroid and hypothyroid patients. The aims of this study were to determine the activities of serum creatine kinase (CK) and lactate deydrogenase (LDH) in thyroid disorders, and to evaluate the relationship between CK, LDH and FT4, and TSH levels. MATERIALS AND METHODS: In this retrospective study, thyroid function tests, serum CK and LDH activities were obtained from the medical records of newly diagnosed hyperthyroid and hypothyroid patients attending the Endocrinology Clinic at the University Hospital of the West Indies from 2005- 2009. RESULTS: Elevation of CK activity was found in 5 patients (28%, 5/18) with overt hypothyroidism and in 12 patients (24.0%, 12/50) with subclinical hypothyroidism. The mean CK activity in subclinical hypothyroid patients was 179.80 ± 125.68 U/L compared with 389.901 ± 381.20 U/L in overt hypothyroid patients. The elevation of LDH activity was found in 6 patients (33.3%, 6/18) with overt hypothyroidism and in 37 patients (74.0%, 37/50) with subclinical hypothyroidism. In the hypothyroid patients, a positive correlation was found between CK activity and TSH (r = 0.292, P = 0.015), and a negative correlation between CK activity and FT4 (r = - 0.325, P = 0.007); and between FT4 and TSH (r = - 0.371, P = 0.002). CONCLUSION: The significant elevation in serum CK and LDH activities indicates that these can be used as parameters for screening hypothyroid patients but not hyperthyroid patients.

Environmental risk factors associated with leptospirosis among butchers and their associates in Jamaica.

BACKGROUND: Leptospirosis, a spirochetal zoonosis, is considered an occupational disease of persons engaged in agriculture, sewage works, forestry, and butchery. OBJECTIVE: To determine the environmental sources and the knowledge, attitude and practices for leptospirosis among butchers and slaughterhouse workers, as well as the seroprevalence of leptospirosis among cattle and pigs presented for slaughter. METHODS: Using an interviewer administered questionnaire, all 110 butchers and other slaughterhouse workers in the parishes of Kingston and St. Andrew, Jamaica were surveyed. In addition, 179 blood samples from animals presented for slaughter were tested for anti-Leptospira antibodies using the microscopic agglutination test (MAT). RESULTS: Analyses indicated that people with the studied occupations are at risk for developing leptospirosis due to several environmental risk factors that exist in slaughterhouses. Among the risk factors, limited knowledge of the disease and its transmission, lower educational level attained, younger age and unhealthy behaviors (e.g., hand washing and improper or lack of use of personal protective gears), presence of stray dogs and rodents, and inadequate maintenance of physical plants, were found to be important. Of the total number of animal samples tested, 20 (11%) were positive. Canicola and Hardjo (among cattle) and Bratislava (among pigs) were the major seroreactors. CONCLUSION: Butchers and slaughterhouse workers engaged in animal handling and slaughtering could be frequently exposed to leptospirosis, and hence control strategies targeting at these populations should be implemented.

The importance of bone biomarkers in the diagnosis of renal osteodystrophy / Importancia de los biomarcadores óseos en el diagnóstico de la osteodistrofia renal

OBJECTIVE: To evaluate the association of serum biochemical markers in patients with chronic kidney disease (CKD) in Jamaica for early detection of renal osteodystrophy (ROD). METHODS: The study contained two groups: CKD group (221) which consisted of adult patients, from dialysis units and renal clinics, with stage III to V CKD. The control group (23 7) had adult individuals, from the medical outpatient clinics, with mild and controlled chronic diseases and absence ofrenal failure. The patients in the study were between 18-80 years of age and gave informed consent to participate in the study. The differences in distribution of demographic, clinical and pathologic variables between the two groups were evaluated. Pearson's chi-squared test and Spearman' rho correlation coefficient test was used, with p < 0.01 considered statistically significant. Data analysis was conducted using the statistical package for the social sciences (SPSS) version 17.0. RESULTS: Among the 221 CKD patients in the study, 174 (78.7%) had ROD based on serum intact parathyroid hormone (iPTH) levels. The majority of patients in the control group did not have bone disease ie 95-96%. The majority of CKD patients (70.0%) had high-turnover (HTO) bone disease compared to 29.3% of patients with low-turnover (LTO) bone disease. Dialysis patients who had HTO bone disease compared with those with LTO had significantly higher levels of iPTH and total serum alkaline phosphatase (ALP). A similar relationship was observed among CKD patients not on dialysis. There was a significant individual variation in bone turnover biochemical markers. A total of237patients were recruited in the control group. Based on the levels of iPTH and tALP, six ofthem were found to have bone disease. The majority ofthese patients with bone disease were diabetic (83.3%) while the other patient had cancer (16.7%). The six patients in the control group with bone disease were within the age cohort of64-80 years, most ofwhom were 78 years old. CONCLUSION: A combination of serum biochemical markers might predict underlying renal osteodystrophy better that would individual biochemical markers. A predictive model using bone histology and biochemical markers can be developed in the future.

OBJETIVO: Evaluar la asociación de marcadores bioquímicos séricos en pacientes con la enfermedad renal crónica (ERC) en Jamaica, para la detección precoz de la osteodistrofia renal (ODR). MÉTODOS: El estudio comprendió dos grupos: un grupo ERC (221) formados por pacientes adultos, provenientes de las unidades de diálisis y las clínicas renales, y en las fases III a V de la ERC. El grupo control (237) estaba constituido por individuos adultos, provenientes de las clínicas ambulatorias médicas, con enfermedades crónicas moderadas y controladas, y sin insuficiencia renal. Los pacientes del estudio tenían edad que fluctuaban de 18 a 80 años de edad y dieron consentimiento informado para participar en el estudio. Se evaluaron las diferencias en la distribución de las variables demográficas, clínicas y patológicas entre los dos grupos. SE usaron la prueba de chi-cuadrado de Pearson y la prueba de coeficiente de correlación rho de Spearman, considerándose p < 0.01 estadísticamente significativa. El análisis de los datos se llevó a cabo usando paquete que usó el paquete estadístico para las ciencias sociales (SPSS) versión 17.0. RESULTADOS: De los 221 pacientes de ERC en el estudio, 174 (78.7%) tenían ODR, basado en los niveles de hormona paratiroidea intacta (PTHi) sérica. La mayor parte de los pacientes en el grupo de control, ie. 95-96%, no tenían enfermedades óseas. La mayoría de los pacientes con ERC (70.0%) presentaban la enfermedad de alto recambio óseo (ARO) en comparación con 29.3% de pacientes con la enfermedad de bajo recambio óseo (BRO). Los pacientes de diálisis con alto recambio óseo - comparados con los de bajo recambio óseo - tuvieron niveles significativamente más altos PTHi y fosfatasa alcalina sérica total (FASt). Una relación similar se observó entre pacientes de ERC sin tratamiento de diálisis. Hubo una variación individual significativa en los marcadores bioquímicos de recambio óseo. Un total de 237 pacientes fueron reclutados para el grupo de control. Sobre la base de los niveles de PTHi y FASt, se hallaron seis con la enfermedad ósea. La mayoría de estos pacientes con enfermedad ósea eran diabéticos (83.3%) mientras que el otro paciente tenía cáncer (16.7%). Los seis pacientes en el grupo de control con enfermedad ósea estaban dentro de la cohorte de 64-80 años de edad, en la que la mayoría tenía 78 años. CONCLUSIÓN: Una combinación de marcadores bioquímicos séricos podrían predecir una osteodistrofia renal subyacente mejor que los marcadores bioquímicos individuales. En el futuro puede desarrollarse un modelo de predicción que use marcadores tanto bioquímicos como histológicos del tejido óseo.

Knowledge, awareness and compliance with universal precautions among health care workers at the University Hospital of the West Indies, Jamaica.

BACKGROUND: Universal precautions are not well understood or implemented by health care practitioners, though crucial in the prevention and transmission of blood-borne pathogens like HIV. OBJECTIVE: To assess knowledge, awareness and compliance of universal precautions among health care workers at the University Hospital of the West Indies, Jamaica. METHODS: A cross-sectional survey was conducted in September and October 2007. A 28-item self-administered questionnaire was provided to 200 health care workers including medical doctors, medical technologists, nurses and porters to assess their knowledge, awareness and practice towards universal precautions. RESULTS: Almost two-thirds (64.0%) of the respondents were very knowledgeable of universal precautions with significantly more females (75.4%) than males (42.9%) (p<0.0001). More nurses (90.0%), medical doctors (88.0%) and medical technologists (70%) were very knowledgeable of universal precautions (p<0.0001). More respondents (92.9%) who were employed in the health sector for 16 years and over reported high levels of awareness of universal precautions than those who were employed for less than five years (p<0.0001). 28.6% of males and only 6.2% of females reported that they do not use protective gear. More nurses reported frequent use of protective equipment followed by medical technologists and medical doctors (p<0.0001). CONCLUSION: There was adequate knowledge and a fair level of awareness among medical doctors, medical technologists, and nurses towards universal precautions.

The importance of bone biomarkers in the diagnosis of renal osteodystrophy.

OBJECTIVE: To evaluate the association of serum biochemical markers in patients with chronic kidney disease (CKD) in Jamaica for early detection of renal osteodystrophy (ROD). METHODS: The study contained two groups: CKD group (221) which consisted of adult patients, from dialysis units and renal clinics, with stage III to V CKD. The control group (237) had adult individuals, from the medical outpatient clinics, with mild and controlled chronic diseases and absence of renal failure. The patients in the study were between 18-80 years of age and gave informed consent to participate in the study. The differences in distribution of demographic, clinical and pathologic variables between the two groups were evaluated. Pearson's chi-squared test and Spearman' rho correlation coefficient test was used, with p < 0.01 considered statistically significant. Data analysis was conducted using the statistical package for the social sciences (SPSS) version 17.0. RESULTS: Among the 221 CKD patients in the study, 174 (78.7%) had ROD based on serum intact parathyroid hormone (iPTH) levels. The majority of patients in the control group did not have bone disease ie 95-96%. The majority of CKD patients (70.0%) had high-turnover (HTO) bone disease compared to 29.3% of patients with low-turnover (LTO) bone disease. Dialysis patients who had HTO bone disease compared with those with LTO had significantly higher levels of iPTH and total serum alkaline phosphatase (ALP). A similar relationship was observed among CKD patients not on dialysis. There was a significant individual variation in bone turnover biochemical markers. A total of 237 patients were recruited in the control group. Based on the levels of iPTH and tALP six of them were found to have bone disease. The majority of these patients with bone disease were diabetic (83.3%) while the other patient had cancer (16.7%). The six patients in the control group with bone disease were within the age cohort of 64-80 years, most of whom were 78 years old. CONCLUSION: A combination of serum biochemical markers might predict underlying renal osteodystrophy better that would individual biochemical markers. A predictive model using bone histology and biochemical markers can be developed in the future.

Effects of S-nitroso-N-acetyl-penicillamine administration on glucose tolerance and plasma levels of insulin and glucagon in the dog.

It has been suggested that nitric oxide (NO, nitrogen monoxide) is a regulator of carbohydrate metabolism in skeletal muscle. The present study was undertaken to investigate the acute effects of the nitric oxide donor S-nitroso-N-acetylpenicillamine (SNAP) on blood glucose levels and on the gluco-regulatory hormones insulin and glucagon in healthy dogs. The acute effects of SNAP on mean arterial pressure and heart rate were also investigated. The drug was administered intravenously and the pre- and postprandial blood glucose, plasma insulin, and glucagon concentrations were determined at half-hour time intervals postadministration after a glucose challenge. The plasma nitrate and nitrite concentrations were measured and taken as the biochemical markers of in vivo NO formation. The oral glucose tolerance test revealed an impaired glucose tolerance in SNAP-treated dogs as reflected by the area under the glucose curve, 1150.50 +/- 63.00 mmol x 150 min and 1355.25 +/- 102.01 mmol/L x 150 min in dogs treated with 10 and 20 mg/kg of SNAP, respectively, compared with 860.25 +/- 60.68 mmol/L x 150 min in captopril-treated controls (P < 0.05). The 2-h blood glucose concentration in dogs treated with 20 mg/kg body wt of SNAP was 9.17 +/- 1.10 mmol/L compared with 5.59 +/- 0.26 mmol/L for captopril-treated controls (P = 0.015). The oral glucose tolerance test also confirmed an impaired insulin secretion in the SNAP-treated dogs. While the plasma insulin concentration increased gradually in the captopril-treated controls to a peak value of 39.50 +/- 2.55 microIU/ml, 1.5 h after a glucose challenge there was a decrease in the plasma insulin concentration in SNAP-treated dogs to a low value of 20.67 +/- 0.88 microIU/ml (P = 0.006). In contrast, there were no significant differences in plasma glucagon concentration in SNAP-treated dogs and captopril-treated dogs at any time points. Using the Griess reaction, we found that there was a 27-95% increase in plasma nitrate/nitrite concentration on administration of SNAP. The sustained hyperglycemic effect observed in SNAP-treated dogs was accompanied by a marginal decrease in the mean arterial blood pressure and a significant increase in heart rate (P < 0.05). We conclude that acute administration of SNAP in the oral glucose tolerance test releases NO that modulates the parameters of carbohydrate metabolism.