Fig 1 - uploaded by Zeman Michal
Content may be subject to copyright.
Daily profiles of heart rate (A), locomotor activity (B) and blood pressure (C) in a laboratory rat implanted with the sensor TA11PA-C40 (DSI St. Paul, Minnesota, USA). Plots represent outputs from the program Dataquest A.R.T. 4.1 with 8.640 values per 24 h reflecting 1 min averages of measured parameters. Animals were kept at LD 12:12, with lights on from 22:00 till 10:00. The dark bar above graphs represents the dark time period
Source publication
Evaluation of physiological traits in freely moving animals represents an innovative approach allowing physiological studies in
undisturbed animals without interference with handling and stress. This approach is important in behavioural sciences and research
on physiological basis of cardiovascular diseases. Recently, there is only one such system...
Similar publications
Little is known about the migration ecology of the American woodcock (Scolopax minor). From 2001 to 2003, we began a 3-year study to document woodcock fall migration routes, rates, and habitat use from Minnesota, Wisconsin, and Michigan, USA. Some 586 radiomarked woodcock initiated migration. During 224 hours of aerial telemetry, we located 42 radi...
In this paper, we present an active rectifier with high power conversion efficiency (PCE) implemented in a 0.5- mum 5 V standard CMOS technology with two modes of built-in back telemetry; short- and open-circuit. As a rectifier, it ensures a PCE > 80%, taking advantage of active synchronous rectification technique in the frequency range of 0.125-1...
Citations
... In the presented study, significant increase in LVEDP together with protected LV systolic function (characterized with mild reduction in EF) is in line with heart failure with preserved EF [3]. Although we observed a significant decrease in MBP after MI, this decrease is within physiological limits and does not reflect a significant hypotension [21]. ...
Background and objective: Heart failure (HF) is a common
complication of cardiovascular disease, which leads to functional cardiac
abnormalities. Beta-blockers are commonly used to reduce mortality in HF
patients; however, they are associated with an increased risk of erectile
dysfunction (ED). Nebivolol is a third-generation beta-blocker with also having a
Nitric oxide (NO) releasing effect. NO plays a key role in penile erection. The
aim of this study was to investigate the NO-mediated effects of nebivolol on ED
in HF.
Material and methods: Twenty-four weeks old rats were divided
into three groups: sham-operated control (SC), HF-induced control (HFC), and
nebivolol-treated (HFNEB). HF was induced by the ligation of the left anterior
descending coronary artery. Eight weeks after the ligation, functional,
hemodynamic, biologic, and histologic studies were conducted to assess
NO-mediated effects of nebivolol.
Results: HF rats displayed impaired erectile function
represented by decreased intracavernosal/mean arterial pressure ratio (ICP/MAP).
Increased nitrosative damage/decreased antioxidant capacity was consistent with
decreased endothelial NOS (eNOS) and increased inducible NOS (iNOS) and neuronal NOS (nNOS) immunoreactivity in this group.
Nebivolol treated animals were characterized by improved functional capacity,
increased antioxidant and decreased oxidant capacity. Prevention of eNOS and an
increase in nNOS immunoreactivity was also significant in this group.
Conclusion: Our study showed the positive effects of nebivolol
on erectile function in HF. NO-mediated mechanisms behind this effect can be
summarized as eNOS mediated dilation of the cavernous body and nNOS mediated
smooth muscle relaxation. To the best of our knowledge, this study is the first
in the literature to discuss all three NOS isoforms in order to explain the
NO-mediated effects of nebivolol in ED.
... The significant increase in LVEDP, despite the protection of LV systolic function, is in line with the HFpEF model (16). Although we observed a significant decrease in MBP after MI, this decrease is within physiological limits and does not reflect a significant hypotension (17). Our results are in line with Cho et al. (18) and suggest that renal hypoperfusion is not a primary factor in the development of CRS. ...
Objectives:
Despite several proposed mechanisms for the pathophysiology of cardiorenal syndrome (CRS), the exact mechanism remains unclear. Nitrosative stress has been argued as a key mechanism recently. Nebivolol is a beta-blocker with nitric oxide (NO)-releasing effect. In the present study, NO-mediated effects of two different treatment regimes of nebivolol in CRS were studied.
Materials and methods:
Rats were divided into: sham-operated (sham-control), myocardial infarction (MI)-induced, (MI-control) early nebivolol-treated (MI-neb1) and late nebivolol-treated (Mı-neb2) groups. The effects of nebivolol were assessed both in the early and late period of MI by histologic, hemodynamic and biologic studies.
Results:
Developed MI model was in line with the heart failure with preserved ejection fraction. Focal and total tubular damage findings were observed in MI-control group both in early and late period of MI. In parallel, subclinical functional damage was transformed into chronic renal dysfunction in this group. Increased inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) together with decreased neuronal NOS (nNOS) levels were in parallel with the increased inflammation and nitrosative stress biomarkers. Nebivolol effectively prevented both subclinical and clinical nephropathy. There was no statistical difference between the nebivolol treatment regimes.
Conclusion:
The beneficial effects of nebivolol were closely related to the reduction of nitrosative damages as well as hemodynamic alterations. The NO-mediated effects were: prevention of nitrosative damage by decreasing iNOS, preservation of nNOS in order to maintain glomerular filtration rate (GFR), and restoration of eNOS in the late period of MI. On contrary to our previous work, early nebivolol administration had a similar effect with delayed administration of nebivolol on CRS.
... The first technique consists of direct observation using interval and ordinal scales. The second approach to quantify locomotor activity includes video-based systems (Pierce and Kalivas, 1997), infrared light beams recorder (Galani et al., 2001), radiotelemetry system (Molčan et al., 2009), open field test (Daniels et al., 2009) and RW s (Jud et al., 2005). ...
Locomotor behaviour is regarded as a fundamental index of general animal activity.
Circadian rhythms (CRs) of locomotor activity are one of the most prominent biological
rhythms which synchronize to the natural environmental light -dark cycle (LD). The present study aims to develop a reliable and precise setup for long-term recordings of the
CRs in laboratory rodents (e.g. rats, hamsters, and mice). The recording setup consists of accessible running wheels (RW) in animal cages. Revolutions of RW were acquired through a circuit supported by either magnetic reed or inf rared (photocell) switch sensors. Data acquisition and analysis were control led through proper software. In a series of experiments, the CRs patterns were successfully recorded under LD, as well as
constant darkness (DD) conditions. In summary, the recording setup enabled, with an acceptable precision, to record and analyses the animal 's circadian locomotor activity patterns automatically without upsetting its behaviour pattern. Measurements and analysis of CRs of locomotor activities using this setup could be applied in various
research issues such as chronobiological, neuroethological, physiological, and
pharmacological studies.Egypt. J. Exp. Biol. (Zool.
... The catheter was then stabilized to the aorta with tissue glue (3M Vetbond; DSI, USA) and a cellulose patch (Cellulose Patch Kit -Small Animals; DSI, USA). The body of the 1ransmitter was secured to the muscular wall and the whole procedure has been validated at our department previously (Molcan et al. 2009). Animals were inclllded in the experiment two weeks after the surgical procedure. ...
Disturbed circadian activity of the sympathetic system may be involved in negative consequences of chronodisruption on the cardiovascular system. We studied daily changes in pressure response to adrenergic stimulation in rats exposed to repeated phase advance shifts (PAS) of light/dark (LD) regimen. Blood pressure (BP), heart rate (HR) and locomotor activity was measured by radiotelemetry in normotensive Wistar rats exposed to repeated PAS (three 8-h shifts per week) lasting for 12 weeks. Norepinephrine was administered subcutaneously in the middle of L and D during week 12 of PAS exposure. In the control LD cycle, cardiovascular parameters exhibited significant daily rhythms with expected higher values during D than L phase. Rats exposed to PAS showed disturbed rhythms without a BP and HR increase. Administration of norepinephrine to control rats revealed daily variability in the cardiovascular response with higher stimulation of BP during L than D. This daily pattern of BP response to norepinephrine was diminished in the PAS group. The damped daily variability in pressure response to norepinephrine and augmented response during the light phase of the day suggest that the increased and desynchronised activity of the sympathetic system may worsen responses of the cardiovascular system to load in individuals exposed to irregular LD conditions.
Although exercise is usually associated with beneficial effects on physical and mental health, patients recovering from surgery may be hampered to perform active exercise. Whole body vibration (WBV) is suggested a passive alternative for physical training. Aim of the present study was to explore the therapeutic potential of WBV compared to physical exercise during early post-surgery recovery.
Male three months old Wistar rats underwent major abdominal surgery. Starting the day after surgery, rats were subjected to either daily WBV or exercise (treadmill running) for 15 consecutive days. Control rats underwent pseudo treatment. During the first week after surgery, effects of interventions were obtained from continuous recording of hemodynamic parameters, body temperature and activity (via an implanted transducer). Behavioral tests were performed during the second post-surgical week to evaluate anxiety-like behavior, short and long-term memory functions, cognitive flexibility and motor performance. Animals were sacrificed 15 days after surgery and brain tissue was collected for analysis of hippocampal neuroinflammation and neurogenesis.
Surgery significantly impacted all parameters measured during the first post-surgery week, irrespective of the type of surgery. Effect on cognitive performance was limited to cognitive flexibility; both WBV and exercise prevented the surgery-induced decline. Exercise, but not WBV increased anxiety-like behavior and grip strength. WBV as well as exercise prevented the surgery-induced declined neurogenesis, but surgery-associated hippocampal neuroinflammation was not affected.
Our results indicated that active exercise and WBV share similar therapeutic potentials in the prevention of surgery induced decline in cognitive flexibility and hippocampal neurogenesis. In contrast to exercise, WBV did not increase anxiety-like behavior. Since neither intervention affected hippocampal neuroinflammation, other mechanisms and/or brain areas may be involved in the behavioral effects. Taken together, we conclude that WBV may provide a relevant alternative to active exercise during the early stage of post-operative recovery.
Embryos of rats with inherited stress-induced arterial hypertension (ISIAH strain) were transferred to normotensive Wistar rats. Cryopreservation of these embryos was used in some trials. Rats developed to term after freezing-thawing of ISIAH embryos and their transfer to Wistar recipients demonstrated a significant decrease in arterial blood pressure (ABP) both in males and females under basal conditions and stress. The effect persisted in subsequent generation obtained from crosses between these animals. In the control series (cryopreservation omitted), transferring of ISIAH embryos to Wistar recipients did cause a decrease; but even ABP increased in offspring. In this experimental series of transferring the unfrozen embryos, ABP of recipient Wistar rats was significantly increased. We have also found behavioral differences between cryopreserved and control rats. Startle reflex was decreased in offspring developed after cryopreservation and embryo transferring of ISIAH rats to Wistar recipients, as compared to initial ISIAH and Wistar rats. Taken together, these experimental data strongly support the hypothesis that embryo freezing and embryo transferring can have delayed consequences for offspring as well as for recipients.
The effects of assisted reproductive technologies on the development of hypertensive phenotype were reviewed. Special attention was paid to the effects of cultivation and transplantation of preimplantation embryos on arterial pressure in individuals developed from these embryos. The analysis of studies performed on the laboratory models (mostly on hypertensive strains of rats) was performed. These data were discussed in the context of application of assisted reproductive technologies in medicine.
Cardiovascular parameters, such as blood pressure and heart rate, exhibit both circadian and ultradian rhythms which are important for the adequate functioning of the system. For a better understanding of possible negative effects of chronodisruption on the cardiovascular system we studied circadian and ultradian rhythms of blood pressure and heart rate in rats exposed to repeated 8 h phase advance shifts of photoperiod. The experiment lasted 12 weeks, with three shifts per week. Spectral power as a function of frequency for both circadian and harmonic ultradian rhythms was expressed as the circadian-ultradian power ratio. The circadian rhythms of blood pressure, heart rate and locomotor activity were recorded during the control light:dark (LD) regimen with higher values during the D in comparison with the L. Phase advance shifts resulted in a diminished circadian-ultradian power ratio for blood pressure, heart rate and locomotor activity indicating suppressed circadian control of these traits greater in heart rate than blood pressure. In conclusion, rats kept under irregular LD conditions have suppressed circadian control of heart rate, blood pressure and locomotor activity and rely more on an acute response to the LD regime. Their ability to anticipate regular loads can be weakened and in this way chronodisruption can contribute to the pathogenesis of cardiovascular diseases.