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Simple Summary: Since there is a lack of information regarding how epoprostenol, a prostacyclin, affects canine renal blood flow (RBF), we investigated the effects of short-term administration of epoprostenol at human doses of 2, 5, and 10 ng/kg/min intravenously for 20 min on RBF in six healthy dogs under anesthesia. The effects of short-term administration were investigated. As the dose of epoprostenol increased, peak systolic and end diastolic velocities of the renal arteries, maximum and minimum venous flow velocities of the interlobular and renal veins, and heart rate all tended to increase. However, these increases were not significant. These results indicate that the administration of human doses of epoprostenol to dogs does not produce significant changes in renal or systemic circulation. Prostacyclin is an in vivo bioactive substance that regulates renal blood flow (RBF). Information regarding how epoprostenol, a prostacyclin preparation, affects RBF in dogs is lacking. We investigated the effects of short-term epoprostenol administration on RBF in six healthy dogs under anesthesia by administering it intravenously at human doses—2, 5, and 10 ng/kg/min for 20 min. RBF was evaluated before and during epoprostenol administration using pulsed Doppler ultrasonography, and renal perfusion was evaluated using contrast-enhanced ultrasonography. Effects on renal and systemic circulation were evaluated by measuring systolic arterial, mean arterial, diastolic arterial, pulmonary arterial, mean right atrial, and pulmonary capillary wedge pressures; heart rate; and cardiac output. Kruskal–Wallis and Bonferroni multiple comparison tests and Spearman's rank correlation coefficient were used for statistical analyses. As epoprostenol dosage increased, the peak systolic and end diastolic velocity of the renal artery, maximum and minimum venous flow velocities of the interlobular and renal veins, and heart rate all tended to increase, although not significantly. Our results indicate that human-dose epoprostenol administration in dogs does not cause significant changes in renal or systemic circulation. However, the human doses used may have been too low to produce a clinical effect in dogs. [ABSTRACT FROM AUTHOR]

Aims Many studies of human subjects have demonstrated the utility of assessing serum levels of endothelin-1 (ET-1) and big ET-1 as clinical biomarkers in cardiopulmonary and neoplastic diseases. In this study we explored the feasibility of using serum big ET-1 as a reliable veterinary marker in dogs with various cardiopulmonary and neoplastic diseases. Main methods Serum big ET-1 levels were measured by ELISA in dogs with cardiopulmonary (n = 21) and neoplastic diseases (n = 57). Dogs exhibiting cardiopulmonary disease were divided into two groups based on the velocity of tricuspid valve regurgitation (3.0 > m/s) measured by ultrasound: without and with pulmonary hypertension. Big ET-1 levels for the dogs with the diseases were compared with levels in normal healthy dogs (n = 17). Key findings Dogs with cardiopulmonary disease (4.6 ± 4.6 pmol/l) showed a significantly ( P < 0.01) higher level of big ET-1 than healthy control dogs (1.1 ± 0.53 pmol/l). Serum levels in the dogs with pulmonary hypertension (6.2 ± 5.3 pmol/l) were significantly ( P < 0.01) higher than those without pulmonary hypertension (2.0 ± 0.6 pmol/l). Dogs with hemangiosarcoma (5.6 ± 2.2 pmol/l), adenocarcinoma (2.0 ± 1.8 pmol/l), histiocytic sarcoma (3.3 ± 1.9 pmol/l), chondrosarcoma or osteosarcoma (3.0 ± 1.6 pmol/l) and hepatocellular carcinoma (2.7 ± 1.8 pmol/l) showed significantly ( P < 0.05) higher levels than healthy control dogs. Significance These findings point to the potential of serum big ET-1 as a clinical marker for cardiopulmonary and neoplastic diseases in dogs. [ABSTRACT FROM AUTHOR]

Highlights: [•] LAT1 is highly expressed in tumors but at low levels in normal tissues. [•] We examine LAT1 expression and function in malignant melanoma (MM). [•] LAT1 expression in MM tissues and cell lines is higher than those in normal tissues. [•] LAT1 selective inhibitors inhibit amino acid uptake and cell growth in MM cells. [•] New chemotherapeutic protocols including LAT1 inhibitors are effective for treatment. [ABSTRACT FROM AUTHOR]

Contrast-enhanced magnetic resonance (MR) imaging with a new liver-specific contrast agent gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA; EOB·Primovist®) was studied in 14 normal beagles and 9 dogs with focal liver lesions. Gd-EOB-DTPA accumulates in normally functioning hepatocytes 20 min after injection. As with Gd-DTPA, it is also possible to perform a dynamic multiphasic examination of the liver with Gd-EOB-DTPA, including an arterial phase and a portal venous phase. First, a reliable protocol was developed and the appropriate timings for the dynamic study and the parenchymal phase in normal dogs using Gd-EOB-DTPA were determined. Second, the patterns of these images were evaluated in patient dogs with hepatic masses. The optimal time of arterial imaging was from 15 s after injection, and the optimal time for portal venous imaging was from 40 s after injection. Meanwhile, the optimal time to observe changes during the hepatobiliary phase was from 20 min after injection. In patient dogs, 11 lesions were diagnosed as malignant tumors; all were hypointense to the surrounding normal liver parenchyma during the hepatobiliary phase. Even with a low-field MR imaging unit, the sequences afforded images adequate to visualize the liver parenchyma and to detect tumors within an appropriate scan time. Contrast-enhanced MR imaging with Gd-EOB-DTPA provides good demarcation on low-field MR imaging for diagnosing canine focal liver lesions. [ABSTRACT FROM AUTHOR]

Objective To evaluate the agreement between cardiac output (CO) values obtained using a transpulmonary thermodilution technique (TPTDCO) and conventional thermodilution technique (TDCO) in anaesthetized dogs with fluid overload. Study design Prospective experimental study. Animals Six healthy Beagle dogs aged 7-8 years. Methods Dogs were anaesthetized with sevoflurane in oxygen, and catheters were inserted for TPTDCO and TDCO measurement. After instrumentation, baseline CO was measured using each technique at a central venous pressure (CVP) of 3-7 mmHg. Dogs were subsequently administered lactated Ringer's solution and 6% hydroxyethyl starch to induce fluid overload. CO measurements were obtained using each technique at CVP values of 8-12 mmHg, 13-17 mmHg, 18-22 mmHg and 23-27 mmHg. Agreements between CO measurements obtained with the respective techniques were analysed using Dunnett's test, Pearson's correlation coefficient and Bland-Altman analysis. Results Thirty pairs of CO values were obtained, ranging from 1.45 L minute−1 to 4.69 L minute−1 for TPTDCO and from 1.30 L minute−1 to 4.61 L minute−1 for TDCO. TPTDCO and TDCO values correlated strongly ( r2 = 0.915, p < 0.001). The bias and mean relative bias between TPTDCO and TDCO were 0.26 ± 0.30 L minute−1 (limits of agreement − 0.29 to 0.81 L minute−1) and 9.7%, respectively. Conclusions and clinical relevance TPTDCO and TDCO measurements obtained in anaesthetized dogs during fluid overload exhibited good agreement. Accordingly, transpulmonary thermodilution provides an accurate measurement of CO in dogs with fluid overload. [ABSTRACT FROM AUTHOR]