The cardiovascular effects of adenosine triphosphate (ATP) as vasodilator was studied in dogs anesthetized with pentobarbital sodium. Eight mongrel dogs with heartworm infection (group F) and 5 healthy dogs as control (group N) were used for the experiment. To determine the severity of heartworm disease, the dogs were examined with electrocardiography and other clinical examinations before the experiment. PaCO₂ was maintained 35-45 mmHg by control ventilation. Mean arterial pressure (MAOP), mean pulmonary arterial pressure (MPAP), heart rate (HR), stroke volume (SV) and cardiac output (CO) were measured. The doses of intravenous infusion of ATP were 50, 100, 200 and 300 pg/kg/ min. Also 1 or 2 mg/kg of ATP was injected rapidly.
The 50 μg/kg/min, of ATP slightly increased in HR and MAOP. More than 100 μg/kg/min. of ATP significantly increased in SV and CO (30±5.4% and 40±8.3%o respectively), and decreased in the total systemic resistance (SVR) and total pulmonary resistance (PVR) (35.1±6.2% and 29.5±10.9% respectively) . More than 200, ccg/kg/min, of ATP significantly decreased not only SVR but also MAOP. MPAP increased at every dose of ATP in group F, but little change was observed in group N with a low dose of ATP.
Though ATP was useful in respect of reduction of the afterload under anesthesia, increased MPAP in groug F suggested that administration of ATP to the dog with heartworm disease requires careful monitoring.

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Transcutaneous oxygen and carbon dioxide tension (tcPO₂ and tcPCO₂) in 5 anesthetized dogs were continuously measured by using a gas monitor PO-550 (Sumitomo Electric Industries, Ltd) . The sensor was attached at the inside of the thigh, and its temperature was maintained at 44°C throughout the experiment. Simultaneously the femoral arterial blood samples were taken for the determination of PaO₂ and PaCO₂. In 4 dogs, concentration of inhalant oxygen gas varied from 100 to 0% step by step at the 10-30 minutes intervals by adding the N₂O gas. In the other dog, abdominal artery was clamped by Satinsky forceps after performing laparotomy. The dog was inhaled the N₂O gas at 31/min for 8 minutes following the inhalation of oxygen gas at 31/min for 10 minutes.
As a result, there was significant correlation between tcPO₂ and PaO₂ (r=0.867-0.899) . But the similar correlation between tcPCO₂ and PaCO₂ was not obtained.
In conclusion, this machine is thought to be a quite useful for the monitoring of respiratory and circulatory conditions in anesthetized dogs.

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A case of canine ureteral ectopia corrected by surgical operation with good recovery was described.
One-year-old female Siberian husky weighing 19kg was presented because of incontinence of the urine for a long time and having malodor recently. Though antibiotic therapy was effective to diminishing the malodor, the incontinence was not improved. Severe bacterial infection of urinary tract was suspected by urinary examination. E. coli was detected in the urine. Intravenous urography showed the ectopic ureters with hydronephrosis and severe ureterectasia on the left side, and ureterectasia on the right side. Laparotomy and cystotomy proved that those enlarged ureters entered under the serosa of urinary bladder obliquely to vesical trigon where they did not open but formed a swelling under the mucosa (ureterocele) . Incision of the swelling proved that those ureters leaded caudally under the mucous membrane of urethral wall. Ureteronephrectomy on the left side was done as the ureterovesical anastomosis usually does not correct the condition of hydronephrosis and ureterectasia. The ureter distal to this trigon incision was ligated by placing sutures through outside. The edges of the incised right ureter were sutured to the cystic mucosa in a simple interrupted pattern. After confirmation of urine flow from right kidney into the urinary bladder, surgical wounds were closed by a routine method. Mild incontinence was observed for 3 months after the operation. Though E, coli was detected in the urine 9 months after the operation, no other problems are seen for these 1.5 years.

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A female mongrel dog (2 months old, 3.4 kg) was presented with a sign of unconsciousness due to automobile accicent. Radiographic and ultrasonic examinations revealed fracture of the skull and subcutaneous hematoma. By surgical intervention, a large hematoma and a part of cerebral cortex prolapsed out of the fractured gap of the frontal bone were removed with some bone fragments. Post-surgical recovery of general physical status, neurological findings and electroencephalography were followed up as long as 3 months after the surgery.
In spite of rather rapid recovery of general physical status, improvement of the gait was less marked. Postual reactions except a hopping reaction were about normal at the 4th week after surgery.
Cranial nervous functions became almost normal by 6th week after surgery, however, visual impairment still remained.
In electroencephalography, many abnormal spikes were obsereved in frontal and vertex areas for first two weeks, however, no abnormal finding was seen for 12 weeks after the surgery.
Body weight increased up to 10 kg at 8th month atter the surgery and the normal first estrus was observed.

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