ABSTRACT. The systolic, mean and diastolic pressures as well as the heart rate were mesured using the oscillometric method, on a total of 104 cats (60 cats in the normal group, and 44 in the renal disease group) which were brought into Azabu University Animal Hospital. The blood pressure in the normal group was systolic: 115.4 ± 10.1 mmHg, mean: 96.2 ± 12.2 mmHg, and diastolic: 73.7 ± 10.7 mmHg. Although no difference in heart rate, the renal disease group showed significantly (p<0.05) higher values for systolic, mean, and diastolic pressure when compared with the normal group. Moreover, when plasma renin activity, angiotensin I and II, and aldosterone concentrations were measured in other cats (11 normal and seven with chronic renal failure), all cats with chronic renal failure showed significantly (p<0.05) higher values than the normal group. It is, therefore, indicated that hypertension due to stimulating renin-angiotensin-aldosterone system may have manifested in cats with renal dysfunction. -KEY WORDS: blood pressure, feline, hypertension, renin-angiotensinaldosterone system. J. Vet. Med. Sci. 60 (7): [805][806][807][808] 1998 vomitus and anemia), and high concentrations (range: 2.1-13.8 mg/dl; mean: 3.9 ± 3.0 mg/dl) of serum creatinine, were classified as the renal disease group. A sphygmomanometer (USM-700GTM : Ueda Electronic Works, Ltd.), oscillometric method, was used to measure the systolic, mean, diastolic pressures and the heart rate in both groups. The blood pressure measurement sites were either the forelimb or the tail, and a measuring cuff was selected based on the size of approximately 40% circumference of the measuring site. In order to avoid stress to the patients as much as possible, blood pressure was measured in an isolated room apart from the regular consulting room. Moreover, the blood pressure was measured a total of five times at one minute intervals with the owner's presence. The results obtained under the physical movements of the patient were deleted from the values as artifacts.The effects of the number of measurements on the blood pressure and heart rate were firstly examined in the normal group. To examine the effects of measuring sites on the blood pressure, the blood pressure of both the forelimb and the tail was compared using a total of 24 cats selected randomly from the normal group. The effects of both gender and age on blood pressure were examined in the normal group. Thereafter, these values obtained from both the normal and the renal disease groups were analyzed.The plasma renin activity, angiotension I and II, and aldosterone concentrations were measured to by radioimmunoassay compare 11 normal to seven cases with chronic renal dysfunction.The statistical analysis on the number of measurements were conducted, first using the Friedman method, followed by the Wilcoxon method. The Speaman raking correlation Hypertension has been recognized as a risk factor in human patients with cerebral hemorrhage, heart and renal diseases, therefore diagnosis of hypertension is carrie...

ABSTRACT. We examined effects of an angiotensin converting-enzyme inhibitor, benazepril hydrochloride (BH), on renal hypertension and chronic renal failure (CRF) in cats. For experimental CRF, healthy cats (n=5) underwent 7/8 renal ablation. After renal insufficiency and hypertension were confirmed by blood urea nitrogen (BUN), serum creatinine, creatinine clearance and telemetric recording of systemic blood pressure, BH was administered orally once daily at 0.9 to 2.0 mg/kg/day for 2 to 3 weeks. Within 2 months after renal ablation, renal failure and hypertension developed as evidenced by significant increases in BUN, serum creatinine and systemic blood pressure (p<0.01 or 0.05) and significantly decreased creatinine clearance accompanied by elevated plasma renin activity, angiotensin I and II, and aldosterone (p<0.01 or 0.05). BH administration corrected systemic hypertension (p<0.05) and significantly reduced angiotensin II and aldosterone (p<0.05). Upon discontinuation of BH, these values returned to the pre-administration levels. Studies on spontaneous CRF enrolled 11 cats with spontaneously occurring CRF. BH was administered orally to 6 cats once daily for 24 weeks at a final dose of 1.0 mg/kg/day, while 5 cats served as control. BH administration reduced serum creatinine and urinary protein concentration in every cat. Results demonstrate that in cats, loss of renal mass leads to activation of the renin-angiotensin-aldosterone system and associated renal hypertension, and indicate that BH is effective in correcting renal hypertension and may provide renal benefits to cats with CRF. KEY WORDS: benazepril hydrochloride, chronic renal failure, feline, hypertension.J. Vet. Med. Sci. 69(10): 1015-1023, 2007 Hypertension can be classified into essential hypertension and secondary hypertension. While the cause of essential hypertension is unknown, the most frequent form of secondary hypertension is renal hypertension [22]. Development of renal hypertension involves retention of body fluid occurring with renal dysfunction, increases in cardiac output and peripheral blood vessel resistance, increased activities of pressor factors, such as the renin-angiotensinaldosterone (RAA) system, and suppression of depressor factors, including the kallikrein-kinin-prostaglandin system [13,37]. Similar to human practice, the incidence of chronic renal failure (CRF) and associated hypertension has been increasing recently in small animal practice [20,29,38], necessitating its diagnostic criteria and therapies.In small animal practice, radical therapies such as kidney transplantation are not practical for the treatment of CRF and, in general, symptomatic and conservative treatments are used in an attempt to improve uremic symptoms and to prevent the progression of renal insufficiency. It has been demonstrated in both experimental animals and humans that hyperactivation of the RAA system and resultant hypertension play a pivotal role in the progression of renal failure [35,43]. In deed, antagonism of the RAA system by either angio...

ABSTRACT. Using the telemetry system, we measured the blood pressure (BP) invasively in seven adult mongrels while unanesthetized and unbound. Post-operative BP after implanting the telemetry BP transmitter showed temporarily high values due to the invasive nature of the surgery. It was, however, observed that BP gradually decreased thereafter, and showed settled trends from the eighth day postoperatively. When we took the average of the systolic, mean and diastolic BP at hourly intervals for each of the dogs once their BP had settled, a twin peak diurnal variation (at 8:00 and 19:00) was observed. Moreover, significantly high values (p<0.05) were identified in active state compared with when sleeping or at rest. The 24 hr BP measured by the telemetry system in seven normal dogs resulted in the following values: systolic 123.4 ± 7.9 mmHg, mean 91.1 ± 5.6 mmHg, and diastolic 74.5 ± 4.9 mmHg.-KEY WORDS: blood pressure, canine, diurnal variation.J. Vet. Med. Sci. 61(6): 643-647, 1999 were exposed under anesthesia, and BP measuring transmitter (model TL10M2-D70) catheter was indwelled. The transmitter body was implanted into a subcutaneous pocket that had created first. After examining the BP by use of transmitter, the digital signal was received by a receiver (RLA2000), and was sent in turn to a consolidation matrix (BCM-100), and a universal adapter (UA10). Finally, the digital signal was converted to an analogue signal by the universal adapter, and output to an analytical computer system (Softron ECG Processor SBP4.8:Softron Co., Tokyo, Japan) (Fig. 1). Further, the systolic, mean and diastolic BP were calculated from the continuous BP readings input for approximately 10 sec at a time at 5 min intervals, and the average were taken to be the systolic, mean and diastolic values for each hour. These measurements were taken continuously for 24 hr, and the following examinations were conducted. Examination of the BP changes after implanting transmitter:We examined the effect of the invasive surgery on BP after the transmitter had been implanted for 14 days post-operatively. For the BP examination, we used the total and average values (24 hr BP) taken every 24 hr using the systolic, mean and diastolic pressure measured at 5 min intervals.Examination into the diurnal BP variations: We examined the diurnal BP variations in normal dogs for a period of seven days after at least one month had passed since the transmitter were implanted. First of all, the systolic, mean and diastolic BP were measured at 5 min intervals and totaled in hourly blocks and examined using their average values. In order to observe the relationship between BP and activity, a comparison was made among the sleeping period (1:00-6:00), the resting period (12:00-17:00), awaking but comparatively settled period, and the periods of intense activity (7:00-9:00 and 18:00-20:00). In addition, comparisons were also made with both the 24 hr BP and For measuring blood pressure (BP) in awake dogs, there are either invasive method by arterial puncture or nonin...

ABSTRACT. Blood pressure (BP) was analyzed invasively using the telemetry system in unanesthetized, unrestrained healthy adult mongrel cats. After surgical implantation of a telemetry transmitter, BP was transiently elevated due to the invasive nature of the surgery, but it was gradually decreased. BP was largely stabilized seven to ten days postsurgery. Once BP was settled, systolic, diastolic and mean BPs 2 were obtained at 5-min intervals in individual cats. Hourly averages of these BP values revealed a diurnal variation with two peaks at 8:00 and 19:00. We also found that BP was significantly higher when cats were active compared to when they were sleeping or at rest (p<0.05). The average 24-hr BP in 20 healthy cats was 118.4 ± 11.0 (systolic), 78.0 ± 8.7 (diastolic) and 94.8 ± 9.5 mmHg (mean) by the telemetry system. KEY WORDS: blood pressure, feline, diurnal variation.J. Vet. Med. Sci. 68(3): 243-248, 2006 Currently blood pressure (BP) is commonly measured in cats by noninvasive methods such as oscillometry and Doppler ultrasonography in the clinical setting [3,12,13,15]. Accurate and stable BP measurements, however, have been difficult with these indirect techniques, because cuff placement and restraint can be very stressful to animals and may interfere with BP readouts. The results may also be variable among methods and operators. In addition, because BP is constantly affected by various factors, it is difficult to reliably evaluate BP of an animal based on a single measurement. To solve these problems, it is necessary to understand the diurnal pressure pattern in cats.Circadian rhythmic or diurnal variations of BP have been known in humans and mice [1,22,23]. We have previously shown that dogs also have diurnal BP variations using a telemetry system that continuously monitors BP for 24 hr without anesthetizing or restraining the animals [16]. On the other hand, only a handful of studies have documented circadian BP patterns in healthy, unrestrained cats. Brown et al. have reported changes in diurnal BP patterns in six healthy cats after administration of certain vasoactive agents [7]. The study by Sei et al. has focused on BP changes during paradoxical sleep and slow-wave sleep in cats [19]. In this study, we monitored BP in 20 healthy cats continuously for a long term by using the stress-free telemetry system. Obtained data were analyzed for diurnal and nocturnal circadian rhythmic patterns and for influences by daily activities. We also addressed whether the 24-hr BP obtained in this study represented the baseline BP in healthy cats. MATERIALS AND METHODS Animals:Twenty adult mixed-breed cats (four males and 16 females) weighing 2.0 to 4.0 kg were used. No abnormalities were found in these animals by general physical examination and blood, serology and urinary tests. They were individually housed in cages for several months prior to the study (for acclimatization) and during the study period under a 12L/12D cycle (light on at 8:00 and off at 20:00). They were given water ad libitum and fed twice da...

ABSTRACT. The oscillometric procedure was used to measure the heart rate as well as the systolic, mean, and diastolic blood pressures of 152 dogs (102 in the control group, 13 in the group with renal disease, 37 in the group with heart disease) who were brought to Azabu University of Veterinary Teaching Hospital. It was demonstrated that the blood pressure and heart rate of the control group lowered and tended to become stable as the number of measurements increased. No appreciable difference was identified in the measurements of either blood pressure or heart rate in the forelimbs and tail head. With regard to gender, males showed a significantly higher value than females (p<0.05). No interaction was identified between age and blood pressure. No difference was identified in the heart rate in all groups. In an investigation of blood pressure in all groups, the renal disease group showed significantly higher values (p<0.05) than either the control or the heart disease group in all values of systolic, mean and diastolic pressures. These results indicated that dogs with renal disease can manifest hypertension. -KEY WORDS: blood pressure, canine, hypertension.