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Background: Previous studies employing polymeric micelles and molecular imaging for in vivo nanosystem characterization have led to the development of radionanoprobes (RNPs) designed for diagnosing and monitoring therapeutic interventions in preclinical oncology research, specifically within breast and colon cancer models. These models exhibit high GLUT1 expression on tumor cells and VEGFR expression on the tumor vasculature. We aimed to enhance the tumor-targeting specificity of these RNPs by functionalizing micelles with glucose and bevacizumab. The choice of 99m Tc to label the nanoprobes is based on its availability and that direct labeling method is a widespread strategy to prepare radiopharmaceuticals using cold reagents and a 99 Mo/ 99m Tc generator. Soluplus ® is an attractive polymer for synthesizing micelles that also allows their functionalization. With all the above, the objective of this work was to design, develop and characterize nanoprobes based on polymeric micelles and radiolabeled with 99m Tc for the characterization of biological processes associated to the diagnosis, prognosis and monitoring of animal models of breast and colon cancer in preclinical research using molecular images., Results: Four RNPs ([ 99m Tc]Tc-Soluplus ® , [ 99m Tc]Tc-Soluplus ® +TPGS, [ 99m Tc]Tc-Soluplus ® +glucose and [ 99m Tc]Tc-Soluplus ® +bevacizumab) were produced with high radiochemical purity (> 95% in all cases) and stability in murine serum for up to 3 h. The RNPs maintained the 100 nm size of the Soluplus ® polymeric micelles even when they were functionalized and labeled with 99m Tc. The image acquisition protocol enabled the visualization of tumor uptake in two cancer experimental models using the assigned RNPs. In vivo biological characterization showed signal-to-background ratios of 1.7 ± 0.03 for [ 99m Tc]Tc-Soluplus ® +TPGS, 1.8 ± 0.02 for [ 99m Tc]Tc-Soluplus ® , and 2.3 ± 0.02 for [ 99m Tc]Tc-Soluplus ® +glucose in the breast cancer model, and 1.8 ± 0.04 for [ 99m Tc]Tc-Soluplus ® and 3.7 ± 0.07 for [ 99m Tc]Tc-Soluplus ® +bevacizumab in the colon cancer model. Ex vivo biodistribution, showed that the uptake of the tumors, regardless of the model, is < 2% IA/g while the blood activity concentration is higher, suggesting that the enhanced permeability and retention effect (EPR) would be one of the mechanisms involved in imaging tumors in addition to the active targeting of RNPs., Conclusions: Soluplus ® -based polymeric micelles provide a promising nanotechnological platform for the development of RNPs. The functionalization with glucose and bevacizumab enhances tumor specificity enabling effective imaging and monitoring of cancer in animal models., (© 2024. The Author(s).)

Cardiovascular diseases remain a leading cause of morbidity and mortality worldwide, requiring innovative therapeutic strategies. This project explores a nano-pharmaceutical approach to enhance the efficacy of cardiovascular drugs, focusing on carvedilol and curcumin. These agents, known for their potential cardiovascular benefits, are encapsulated within Soluplus® micelles to form a novel drug delivery system. The novelty of this formulation lies in its ability to significantly improve the solubility of both carvedilol and curcumin, which have traditionally been limited by their hydrophobic nature. By utilizing Soluplus® micelles, we have developed a unique delivery system that optimizes the therapeutic potential of both drugs. The nanomicelles were meticulously characterized for drug loading, size distribution, and morphological features. The carvedilol and curcumin release patterns were investigated, revealing sustained and controlled release profiles. Additionally, the antioxidant capacity of the micellar formulation was evaluated, demonstrating the preservation of curcumin's antioxidative properties. In vivo studies using spontaneously hypertensive male rats explored the pharmacokinetics and hemodynamic effects of the nanomicellar system. These results indicated successful encapsulation of both drugs without altering their plasma profiles. Furthermore, the administration of carvedilol and curcumin micelles exhibited a more significant reduction in mean arterial pressure compared to individual drug administration, suggesting a potential synergistic effect. In conclusion, this nano-pharmaceutical approach offers a promising avenue for cardiovascular therapy, providing a platform for combined drug delivery and potential synergistic effects. The optimized formulation could lead to improved patient outcomes and enhanced cardiovascular health., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The management of the patient with fever in the intensive cardiac care unit begins with a thorough evaluation of the patient, particularly symptoms, clinical history and physical examination, to provide information regarding the origin of the fever. The global evaluation of the patient should be integrated with blood and microbiological tests, in particular blood culture and swab. The laboratory, microbiologic or radiologic tests could be more or less detailed and targeted depending on the type of suspected infection and clinical conditions of the patient. When therapy is necessary, it is crucial to switch, as soon as possible, from broad spectrum antibiotic therapy to antibiotic therapy based on the results of the microbiological exams. Antibiotic therapy could be associated with antipyretic and specific organ support therapy when necessary.

We report on the use of biochips based on one-dimensional photonic crystals sustaining Bloch surface waves to specifically detect target miRNA that is characteristic of hemorrhagic stroke (miR-16-5p) at low concentration in a buffer solution. The biochips were functionalized with streptavidin and ssDNA oligonucleotides to enable miRNA detection. To discriminate the target miRNA from a non-specific control (miR-101a-3p), we made use of an optical platform developed to work both in label-free and fluorescence detection modes. We demonstrate that the limit of detection provided when operating in the fluorescence mode allows us to specifically detect the target miRNA down to 1 ng mL -1 (140 pM), which matches the recommendations for diagnostic miRNA assays, 5 ng mL -1 . The low costs open the way towards the application of these disposable optical biochips based on 1DPC sustaining Bloch surface waves as a promising tool for early disease detection in a liquid biopsy format.

Background: Cystic fibrosis (CF), which is caused by mutations in the CF transmembrane conductance regulator (CFTR), is characterised by chronic bacterial lung infection and inflammation. In CF, monocytes and monocyte-derived macrophages have been shown to display defective phagocytosis and antimicrobial activity against relevant lung pathogens, including Pseudomonas aeruginosa . Thus, we addressed the effect of CFTR triple modulator therapy (elexacaftor/tezacaftor/ivacaftor (ETI)) on the activity of CF monocytes against P. aeruginosa ., Methods: Monocytes from people with CF (PWCF) before and after 1 and 6 months of ETI therapy were isolated from blood and infected with P. aeruginosa to assess phagocytic activity and intracellular bacterial killing. The oxidative burst and interleukin-6 secretion were also determined. Monocytes from healthy controls were also included., Results: Longitudinal analysis of the clinical parameters confirmed an improvement of lung function and lung microbiology by ETI. Both the phagocytic and microbicidal deficiencies of CF monocytes also improved significantly, although not completely. Furthermore, we measured an exuberant oxidative burst in CF monocytes before therapy, which was reduced considerably by ETI. This led to an improvement of reactive oxygen species-dependent bactericidal activity. Inflammatory response to bacterial stimuli was also lowered compared with pre-therapy., Conclusions: PWCF on ETI therapy, in a real-life setting, in addition to clinical recovery, showed significant improvement in monocyte activity against P. aeruginosa , which may have contributed to the overall effect of ETI on pulmonary disease. This also suggests that CF monocyte dysfunctions may be specifically targeted to ameliorate lung function in CF., Competing Interests: Conflict of interest: All authors have nothing to disclose., (Copyright ©The authors 2023.)

Supplementation with Coenzyme Q 10 (CoQ 10 ), in patients with its deficiency, has greater odds of success if the treatment is carried out early with an appropriate formulation. For neonatal CoQ 10 deficiency, infant formula supplementation could be an attractive option. However, solid CoQ 10 cannot be solubilized or dispersed in milk matrix leading to an inefficient CoQ 10 dosage and poor intestinal absorption. We developed and characterized a high-dose CoQ 10 oil-in-water (O/W) nanoemulsion suitable to supplement infant formula without modifying its organoleptic characteristics. CoQ 10 powder and soy lecithin were solubilized in an oil phase consisted of Labrasol® and Labrafac TM . The aqueous phase was Tween 80, TPGS, methylparaben and propylparaben. O/W nanoemulsion was prepared by adding dropwise the oil phase to the aqueous phase under stirring to a final concentration of CoQ 10 9.5 % w/w followed by ultrasonic homogenization. Pharmacotechnical parameters were determined. This formulation resulted to be easily to be dispersed in milk matrix, stable for at least 90 days, with no cytotoxicity in in vitro assays, and higher bioavailability than CoQ 10 powder. CoQ 10 nanoemulsion supplementation in the infant formula facilitates the individualized administration for the child with accurate dosage, overcome swallowing difficulties and in turn could increase the treatment adherence and efficacy., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The number of elderly patients admitted to cardiac intensive care units (CICU) is significantly increasing. Nowadays, novel diagnostic and therapeutic tools allow to treat the vast majority of cardiac acute diseases, nonetheless care of elderly patients requires a careful clinical evaluation. A favorable proportion of cost-effectiveness is warranted, aimed at avoiding futile procedures or treatments. On the other hand, the availability of minimally invasive procedures carries forward old limits to treatments in elderly patients in CICU. It appears evident that age cannot per se represent a limit in the care of elderly people. The present review gives insights in the management of the most common cardiovascular disease settings in elderly patients in the CICUs, thus providing important tools in complex decision-making.

Sexual dysfunctions are common side effects reported by patients during antidepressant treatment. When they occur, patients often discontinue psychopharmacological therapy, with a negative impact on the underlying psychiatric disease. Recently, great attention has been paid to the use of nutraceuticals in the management of psychiatric disorders, although a systematic review on their effects as a treatment option for antidepressant-induced sexual dysfunctions (AISD) is lacking. Here, we conducted a systematic search in the following databases: MEDLINE (through PubMed), EMBASE, PsycINFO, Cochrane Central Register of Controlled Trials, and Web of Science. We searched eligible studies among parallel or crossover randomized controlled trials (RCTs) in adult populations. After this process, a total of 10 articles that evaluated the effect of six different nutraceuticals versus placebo were included: Maca Root, S-adenosyl-L-methionine (SAMe), Rosa Damascena, Ginkgo Biloba, Saffron, and Yohimbine. Overall, a high dose of Maca Root and the use of SAMe or Saffron may improve AISD. Additionally, the administration of Rosa Damascena seemed to be more effective in men than in women, whereas no evidence of effects emerged for Gingko Biloba and Yohimbine. Given the mixed results still available, future RCTs should consider larger samples and confounding factors, such as depressive status and individual vulnerability.

The treatment of patients with advanced acute heart failure is still challenging. Intra-aortic balloon pump (IABP) has widely been used in the management of patients with cardiogenic shock. However, according to international guidelines, its routinary use in patients with cardiogenic shock is not recommended. This recommendation is derived from the results of the IABP-SHOCK II trial, which demonstrated that IABP does not reduce all-cause mortality in patients with acute myocardial infarction and cardiogenic shock. The present position paper, released by the Italian Association of Hospital Cardiologists, reviews the available data derived from clinical studies. It also provides practical recommendations for the optimal use of IABP in the treatment of cardiogenic shock and advanced acute heart failure., (Published on behalf of the European Society of Cardiology. © The Author(s) 2021.)

Background: Despite evidence that clinical outcomes for patients treated with peritoneal dialysis (PD) or home haemodialysis are better than for patients treated with conventional satellite or hospital-based haemodialysis, rates of home-based dialysis therapies world-wide remain low. Home-based dialysis care is also cost-effective and indeed the favoured dialysis option for many patients., Methods & Objectives: Using a lean-thinking framework and established change management methodology, a project embracing a system-wide approach at making a change where a 'Home before Hospital' philosophy underpinned all approaches to dialysis care was undertaken. Three multidisciplinary working groups (pathway, outreach and hybrid) were established for re-design and implementation. The primary aim was to improve home-based dialysis therapy prevalence rates from a baseline of 14.8% by ≥2.5%/year to meet a target of 35%, whilst not only maintaining but improving the quality of care provided to patients requiring maintenance dialysis. A 'future' state pathway was developed after review of the 'current' state (Pathway Working Group) and formed the basis on which a nurse-led outreach service (Outreach Working Group) was established. With the support of the multidisciplinary team, the outreach service model focussed on early, consistent, and frequent education, patient support in decision-making, and clinician engagement., Results: A target prevalence of >30% for home-based therapies (mainly achieved with PD) was achieved within 2 years. This prevalence rate reached 35% within 3 years and was maintained at 8 years. In addition, selected patients already on maintenance satellite-based haemodialysis (Hybrid Working Group) were educated to achieve high levels of proficiencies in self-care., Conclusion: Having the system-wide approach to a Quality Improvement Process and using established principles and change management processes, the successful implementation of a new sustainable model of care focussed on home-based dialysis therapy was achieved. A key feature of the model (through outreach) was early nurse-led education and support of patients in decision-making and ongoing support through multidisciplinary care., (© The Author(s) 2021. Published by Oxford University Press on behalf of International Society for Quality in Health Care. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The treatment of patients with advanced acute heart failure is still challenging. Intra-aortic balloon pump (IABP) has widely been used in the management of patients with cardiogenic shock. However, according to international guidelines, its routinary use in patients with cardiogenic shock is not recommended. This recommendation is derived from the results of the IABP-SHOCK II trial, which demonstrated that IABP does not reduce all-cause mortality in patients with acute myocardial infarction and cardiogenic shock. The present position paper, released by the Italian Association of Hospital Cardiologists (ANMCO), reviews the available data derived from clinical studies. It also provides practical recommendations for the optimal use of IABP in the treatment of cardiogenic shock and advanced acute heart failure. Data deriving from a national survey in Italian hospitals about IABP use are also provided.

Vismodegib is a first-in-class inhibitor for advanced basal cell carcinoma treatment. Its daily oral doses present a high distribution volume and several side effects. We evaluated its skin penetration loaded in diverse nanosystems as potential strategies to reduce side effects and drug quantities. Ultradeformable liposomes, ethosomes, colloidal liquid crystals, and dendrimers were able to transport Vismodegib to deep skin layers, while polymeric micelles failed at this. As lipidic systems were the most effective, we assessed the in vitro and in vivo toxicity of Vismodegib-loaded ultradeformable liposomes, apoptosis, and cellular uptake. Vismodegib emerges as a versatile drug that can be loaded in several delivery systems for topical application. These findings may be also useful for the consideration of topical delivery of other drugs with a low water solubility.

An association between HIV infection and cervical cancer, a major public health issue worldwide, has been reported. The aim of this study was to estimate the prevalence of human papillomavirus (HPV) infection and the distribution of HPV genotypes in HIV-infected women living in French Antilles and Guiana and to determine HIV-related characteristics associated with HPV infection. This cross-sectional study included 439 HIV-infected women who were followed between January 2011 and May 2014. Variables related to HIV infections were collected, and cervical samples were analysed to determine HPV genotypes. The median age of the population was 46 years. Estimated prevalence of HPV and high-risk (HR)-HPV infection were 50.1% IC95 [45.4-54.7] and 42% IC95 [37.3-46.6], respectively. HR-HPV 16, 52, 53 or intermediate risk-HPV-68 were found in 25% to 30% of the HPV-infected patients. Gynaecological screening revealed abnormal cervical smear in 24% and 42% of HR-HPV-negative and HPV-positive women, respectively (p = 0.003). Approximately 90% of women were on antiretroviral therapy (ART). Demographic characteristics associated with a higher prevalence of HPV infection included alcohol consumption. Regarding HIV-related characteristics, current therapy on ART, its duration, and undetectable plasma concentrations of RNA-HIV1 were associated with a lower risk of HPV infection. Infection rate with HR-HPV was higher than what is commonly reported in HIV-negative women worldwide and was more likely in women with incomplete HIV suppression. These results highlight the need for supporting adherence to ART, cervical cytology, HPV testing and HPV vaccination., Competing Interests: The authors have declared that no competing interests exist.

The cardiovascular effects and pharmacokinetics of nebivolol were assessed in N(G)-nitro-l-arginine methyl ester (L-NAME) hypertensive and normotensive control rats. Male Wistar rats were randomly divided to drink tap water (control) or L-NAME solution for 2 weeks. The effects of nebivolol (3 or 10 mg kg(-1) i.v.) on blood pressure (BP), heart rate and BP variability (BPV) were recorded in awake L-NAME and control rats. Short-term and beat-to-beat BPV was assessed by the s.d. and spectral analysis of the BP recordings. Nebivolol pharmacokinetics was studied by means of traditional blood sampling. Nebivolol showed enantioselective pharmacokinetics in both experimental groups; the clearance and the volume of distribution of l-nebivolol were significantly greater than those of the d-enantiomer. The hypotensive response to nebivolol was significantly enhanced in L-NAME rats (Δmean arterial pressure (MAP): -16.1±1.1%, P<0.05 vs. control rats) compared with normotensive animals (ΔMAP: -1.4±2.1%). An analysis of the beat-to-beat BPV showed a greater reduction in VLF BPV in the L-NAME compare with the control rats. Nebivolol significantly reduced the low-frequency/high-frequency ratio in hypertensive L-NAME animals compared with normotensive rats. Short-term BPV was markedly reduced by nebivolol in both experimental groups, although the attenuation of the s.d. of BP recording was greater in L-NAME rats. In conclusion, the hypotensive efficacy of nebivolol is significantly enhanced in L-NAME rats compared with normotensive animals, which is most likely due to a greater reduction in vascular sympathetic activity. Nebivolol markedly attenuated short-term BPV in both experimental groups, suggesting that β-blockers with additional pharmacological actions provide beneficial cardiovascular effects by controlling high BP and its short-term variability.

An increase in blood pressure variability (BPV) contributes to the development of target organ damage associated with hypertension. Treatment with conventional β-blockers, such as atenolol, has been associated with an increase in BPV; however, the extrapolation of these results to third generation β-blockers with pleiotropic effects seems to be inappropriate. The cardiovascular effects of third generation β-blockers, carvedilol and nebivolol, were assessed in sinoaortic-denervated rats (SAD) and compared with the second generation β-blocker atenolol and the calcium channel blocker verapamil, with a special focus on short-term BPV. Male SAD rats were acutely treated with carvedilol, nebivolol, atenolol or verapamil at two different doses, and the effects on blood pressure and BPV were recorded. Short-term BPV was assessed by the s.d. of BP recordings. Beat-to-beat BPV was studied using spectral analysis to assess the vascular sympatholytic activity of carvedilol and nebivolol by estimating the effects of these drugs on the ratio of low frequency (LF) to high frequency (HF) BPV (LF/HF ratio). Nebivolol, carvedilol and the calcium channel blocker verapamil significantly attenuated short-term BPV at both doses in SAD animals, and there were no differences between the drugs. Conversely, atenolol did not modify baseline s.d. values at either dose. Carvedilol and nebivolol significantly reduced the LF/HF ratio in SAD rats compared with the effects of atenolol and verapamil, suggesting the ability of the third generation β-blockers to reduce vascular sympathetic activity. In conclusion, third generation β-blockers induce a marked reduction in short-term BPV in SAD rats compared to atenolol. Moreover, the ability of carvedilol and nebivolol to reduce short-term BPV in SAD rats is equivalent to that of verapamil, suggesting that these β-blockers may have an additional beneficial effect through their control of short-term variability to a similar extent to calcium channel blockers.

Objective: Two clobazam aqueous suspensions for paediatric oral usage (5 mg/ml) were investigated to determinate its physicochemical stability under different storage conditions., Method: Formulations were stored at 4 and 25 °C and the clobazam content was determined by High Performance Liquid Chromatography. Each sample was analyzed by triplicate at different time points (0, 7, 14, 28 and 56 days)., Results: Liquid suspensions were successfully formulated from pure drug and commercially available tablets. In both cases, samples showed suitable physical stability. Clobazam was chemically stable in aqueous suspension during the 56 days of the study at the two storage temperatures., Conclusions: All the tried oral liquid formulations can be conserved at 4 and 25 °C at least 56-day period., (Copyright © 2013 SEFH. Published by AULA MEDICA. All rights reserved.)

It is unknown whether the type and grade of a primary endometrial carcinoma is reliably maintained in recurrence. All matched primary and recurrent endometrial carcinomas diagnosed from 2000 to 2010 at our institution were identified; 34 cases had available slides. Histologic classification was performed using modifications to the World Health Organization criteria. Immunohistochemical analysis for p53, p16, progesterone receptor (PR), and DNA mismatch-repair proteins (MMR) (MLH1, MSH2, MSH6, and PMS2) was performed. Endometrioid carcinoma recurrences were mostly local, whereas serous carcinoma recurrences were mostly peritoneal. Compared with endometrioid carcinoma patients, serous carcinoma patients were older, presented at high stage, and had shorter survival. Serous carcinomas were the most common recurrent endometrial carcinoma (18/34 cases). Overall, 21 cases (62%) displayed similar morphology when comparing primary and recurrent carcinomas, whereas 13 displayed discordant morphology. Seven of 13 endometrioid carcinomas (54%) had a morphologically discordant recurrence, compared with 3 of 14 serous carcinomas (21%), 1 of 4 morphologically ambiguous carcinomas (25%), and both mixed epithelial carcinomas. Serous and morphologically ambiguous carcinomas therefore demonstrated relative morphologic fidelity compared with endometrioid carcinomas. Four morphologically discordant cases demonstrated either pure clear cell carcinoma or clear cell features at recurrence. Seven of 23 matched pairs displayed discordant PR results, with 5 cases, including both endometrioid and serous carcinomas, showing diminished PR expression at recurrence. p53, p16, and DNA MMR staining results were generally concordant when evaluating matched pairs, with only occasional exceptions. Sixty-four percent of all pure endometrioid carcinomas and mixed epithelial carcinomas with an endometrioid component showed loss of expression of MLH1 and/or PMS2; no serous carcinoma demonstrated this abnormality. Clinical and immunohistochemical data supported the use of modifications to the World Health Organization diagnostic criteria. More importantly, the data suggest that when confronted with recurrent endometrial carcinoma, particularly a serous carcinoma, it is reasonable to base therapeutic decisions on the type of the primary tumor, especially if sampling or excising the recurrent tumor is problematic. However, in light of the PR results, sampling a recurrent endometrioid carcinoma may be worthwhile if hormonal therapy is planned. Recurrent endometrioid carcinoma may be enriched for tumors with DNA MMR abnormalities.

Cardiovascular effects and pharmacokinetics of nebivolol were assessed in spontaneously hypertensive rats (SHR) and Wistar Kyoto (WKY) animals. Male SH and WKY rats were treated with vehicle or nebivolol 0.3, 3, or 10 mg kg(-1) (i.v.) and effects on blood pressure (BP), heart rate, and blood pressure variability (BPV) were recorded. Plasma pharmacokinetics of d- and l-nebivolol was studied by traditional blood sampling. Short-term and beat-to-beat BPV was assessed by standard deviation and spectral analysis of BP recording, respectively. Nebivolol showed enantioselective pharmacokinetics in both experimental groups; clearance of l-nebivolol was significantly greater than d-enantiomer. Clearance of nebivolol was significantly reduced in SHR with regards to WKY animals. Hypotensive response to nebivolol 3 and 10 mg kg(-1) was significantly enhanced in SHR compared with normotensive animals. Spectral analysis of beat-to-beat BPV showed a greater reduction in low frequency BPV in SHR than in WKY rats. Nebivolol 3 and 10 mg kg(-1) significantly reduced ratio low frequency/high frequency BPV only in SHR. Short-term BPV was markedly reduced by nebivolol 0.3, 3, and 10 mg kg(-1) in WKY and SHR. In conclusion, the hypertensive stage in SHR modifies nebivolol pharmacokinetic properties and enhances its hypotensive response due to a greater attenuation in vascular sympathetic activity and enhancement of endothelial-derived NO activity. Nebivolol markedly attenuates short-term BPV in both experimental groups providing beneficial cardiovascular effects by both controlling high blood pressure and its short-term variability.

The cardiovascular effects and pharmacokinetics of carvedilol were assessed in spontaneously hypertensive (SH) and Wistar Kyoto (WKY) animals with special focus on short-term blood pressure variability (BPV). Male SH and WKY rats were acutely treated with vehicle or carvedilol 1 or 5 mg kg(-1) (i.v.), and effects on blood pressure (BP), heart rate (HR) and BPV were recorded. Plasma pharmacokinetics of R- and S-carvedilol was studied by traditional blood sampling. Relationship between carvedilol concentrations and their hypotensive and bradycardic effects was established by pharmacokinetic-pharmacodynamic (PK-PD) modelling. Short-term BPV was assessed by standard deviation of BP recording. Vascular sympatholytic activity of carvedilol was studied by estimation of drug effects on ratio between low frequency (LF) and high frequency (HF) BPV (LF/HF ratio). Although pharmacokinetic properties of carvedilol remained mainly unaffected in SH rats with regard to WKY rats, hypertensive animals showed a reduction in drug clearance of R- and S-carvedilol after administration of 1 mg kg(-1) compared with WKY rats. PK-PD analysis of HR changes induced by S-carvedilol showed a greater maximal bradycardic response to carvedilol in SH rats (E (max), -27.6 ± 3.9%; p < 0.05) compared with WKY group (E (max), -13.4 ± 2.5%). SH rats showed a greater hypotensive effect of racemic carvedilol (E (max), -45.5 ± 5.0%; p < 0.05) with regard to WKY group (E (max), -17.9 ± 4.5%). Carvedilol induced a greater reduction of LF/HF ratio in SH rats compared with WKY rats. Short-term BPV was markedly reduced by carvedilol in WKY and SH rats. In conclusion, as a consequence of an enhanced bradycardic response and a greater vascular sympatholytic activity, carvedilol exerts a greater hypotensive response in SH rats compared with WKY animals and dramatically reduces short-term BPV.

Cardiovascular effects and pharmacokinetics of carvedilol were assessed in fructose-fed rats using pharmacokinetic-pharmacodynamic (PK-PD) modeling. Male Sprague-Dowley rats were randomly assigned to receive tap water (C rats) or fructose solution (10% w/v) (F rats) during 6 weeks. Effects of carvedilol (1-3 mg/kg i.v.) on blood pressure, heart rate and blood pressure variability were recorded. Carvedilol plasma pharmacokinetics was studied by traditional blood sampling. Relationship between carvedilol concentrations and their hypotensive and bradycardic effects was established by PK-PD modeling. Vascular sympatholytic activity of carvedilol was assessed by estimation of drug effects on low frequency blood pressure variability using spectral analysis. A greater volume of distribution and clearance of S-carvedilol compared to R-enantiomer was found in both experimental groups. Although PK-PD properties of S-carvedilol chronotropic effect were not altered in F rats, hypertensive rats showed greater efficacy to the carvedilol hypotensive response after administration of the higher dose. A similar potency of carvedilol to inhibit sympathetic vascular activity was found in F rats. Carvedilol showed enantioselective pharmacokinetic properties with increased distribution in F rats compared with normotensive animals. An enhanced hypotensive activity of carvedilol was found in F rats compared with C rats, which is not related to enhance sympatholytic activity.