Protective effect of mirtazapine versus ginger against cisplatin-induced testicular damage in adult male albino rats.

Cisplatin (CP) is a chemotherapy medication used to treat different types of organs cancers. It has damaging effects on testes. Mirtazapine is an antidepressant, which is used primarily in the treatment of depression and other anxiety disorders. Ginger is a naturally growing plant with antioxidant properties. Thirty-six adult male albino rats, subdivided into six groups (six animals each) received treatment for 30 days. Group I (control) received saline solution orally; group II received mirtazapine (20 mg/kg). Group III received ginger (200 mg/kg/day), group IV received CP (7 mg/kg) IP single dose, at day 23rd, group V received mirtazapine (200 mg/day) orally till day 23rd, CP (7 mg/kg) IP at day 23rd, mirtazapine till day 30th, group VI received ginger (200 mg/Kg/day) orally till day 23rd, CP (7 mg/kg) IP at day 23rd, and then ginger at the previous dose till day 30th. This study examined the microscopic changes associated with CP and the possible testicular protective role of mirtazapine versus ginger of adult male rats. Mirtazapine and ginger resulted in cellular protection of testicular tissue as evident from microscopic changes including Sertoli cells, spermatogonia, and Leydig cells. Ginger showed to have a more protective effect than mirtazapine on testicular tissue against CP treatment.

The potential effects of silver and gold nanoparticles as molluscicides and cercaricides on Schistosoma mansoni.

Schistosomiasis seriously affects human health in tropical regions. Its prevention is more important than treatment, raising the need for effective control methods. Recently, the role of nanomaterials in medical science has been growing. The present study aimed to evaluate the potential effects of silver (Ag) and gold (Au) nanoparticles (NPs) on Biomphalaria alexandrina snails and Schistosoma mansoni cercariae in vitro and to assess their effects on the infectivity of cercariae in vivo. The in vitro study proved that Ag and Au NPs were effective in killing B. alexandrina snails, with 30 µg/ml Ag and 160 µg/ml Au causing 100% mortality. The LC50 of 9.68 µg/ml for Ag NPs and 133.7 µg/ml for Au NPs prevented snail infection with S. mansoni miracidia. Furthermore, Ag NPs at 50 µg/ml and Au NPs at 100 µg/ml increased the mortality of S. mansoni cercariae in a dose- and time-dependent manner, reaching 100% mortality after 1 h. The in vivo study found that Ag NPs prevented the occurrence of infection when cercariae were treated before the infection by either the tail immersion (TI) or subcutaneous (SC) route, as proven by parasitological parameters and by the absence of granuloma formation in hepatic tissue. Meanwhile, infection of mice by untreated cercariae followed by treatment with NPs 1 h post-infection (PI) caused a decrease in egg count/g intestine and egg count/g liver in the TI-infected group only. The oogram patterns and granuloma formation results were similar between infection control and the SC-infected group. On the other hand, Au NPs led to a decrease in total worm burden (TWB) in all tested groups, with a decrease in egg count/g intestine and egg count/g liver in TI-infected groups with either pre-treated or post-treated cercariae, in contrast to SC-infected groups. However, the oogram patterns and granuloma formation showed similar results to infection control. Ag and Au NPs have potential as molluscicides and cercaricides in vitro and can prevent or modulate the infectivity of cercariae in vivo.

Management of Barrett's esophagus.

Both the incidence of esophageal adenocarcinoma (EA) and its precursor, Barrett's esophagus (BE) is increasing rapidly in the western world. The progression of BE to EA follows the metaplasia-dysplasia-carcinoma sequence which makes BE the focus of intervention before the development of EA. Considerations are given on the feasibility of a screening program for the population at risk, followed by surveillance of patients found to have BE on endoscopy. Potential management options are then stratified based histological findings of various degrees of dysplasia. This begins with watchful waiting or surveillance as in the case of BE with no dysplasia and low-grade dysplasia (LGD). Ablative therapies such as radiofrequency ablation (RFA) can be considered in non-visible high-grade dysplasia (HGD). With visible lesions and intramucosal cancers, Endoscopic Mucosal Resection (EMR) or Endoscopic Submucosal Dissection (ESD) is generally recommended as a treatment and staging technique. Esophagectomy remains the treatment of choice in EA where there is a high risk of metastasis such as those with deeper submucosal invasion, lymph-vascular or neural invasion and those of higher tumour grade.

Recent Progress in Modification Strategies of Nanocellulose-Based Aerogels for Oil Absorption Application.

Oil spills and oily wastewater have become a major environmental problem in recent years, directly impacting the environment and biodiversity. Several techniques have been developed to solve this problem, including biological degradation, chemicals, controlled burning, physical absorption and membrane separation. Recently, biopolymeric aerogels have been proposed as a green solution for this problem, and they possess superior selective oil absorption capacity compared with other approaches. Several modification strategies have been applied to nanocellulose-based aerogel to enhance its poor hydrophobicity, increase its oil absorption capacity, improve its selectivity of oils and make it a compressible and elastic magnetically responsive aerogel, which will ease its recovery after use. This review presents an introduction to nanocellulose-based aerogel and its fabrication approaches. Different applications of nanocellulose aerogel in environmental, medical and industrial fields are presented. Different strategies for the modification of nanocellulose-based aerogel are critically discussed in this review, presenting the most recent works in terms of enhancing the aerogel performance in oil absorption in addition to the potential of these materials in near future.

Hand pattern indicates prostate cancer risk.

BACKGROUND: The ratio of digit lengths is fixed in utero, and may be a proxy indicator for prenatal testosterone levels. METHODS: We analysed the right-hand pattern and prostate cancer risk in 1524 prostate cancer cases and 3044 population-based controls. RESULTS: Compared with index finger shorter than ring finger (low 2D : 4D), men with index finger longer than ring finger (high 2D : 4D) showed a negative association, suggesting a protective effect with a 33% risk reduction (odds ratio (OR) 0.67, 95% confidence interval (CI) 0.57-0.80). Risk reduction was even greater (87%) in age group <60 (OR 0.13, 95% CI 0.09-0.21). CONCLUSION: Pattern of finger lengths may be a simple marker of prostate cancer risk, with length of 2D greater than 4D suggestive of lower risk.

Functional Properties of Antimicrobial Neem Leaves Extract Based Macroalgae Biofilms for Potential Use as Active Dry Packaging Applications.

Antimicrobial irradiated seaweed-neem biocomposite films were synthesized in this study. The storage functional properties of the films were investigated. Characterization of the prepared films was conducted using SEM, FT-IR, contact angle, and antimicrobial test. The macroscopic and microscopic including the analysis of the functional group and the gas chromatography-mass spectrometry test revealed the main active constituents present in the neem extract, which was used an essential component of the fabricated films. Neem leaves' extracts with 5% w/w concentration were incorporated into the matrix of seaweed biopolymer and the seaweed-neem bio-composite film were irradiated with different dosages of gamma radiation (0.5, 1, 1.5, and 2 kGy). The tensile, thermal, and the antimicrobial properties of the films were studied. The results revealed that the irradiated films exhibited improved functional properties compared to the control film at 1.5 kGy radiation dosage. The tensile strength, tensile modulus, and toughness exhibited by the films increased, while the elongation of the irradiated bio-composite film decreased compared to the control film. The morphology of the irradiated films demonstrated a smoother surface compared to the control and provided surface intermolecular interaction of the neem-seaweed matrix. The film indicated an optimum storage stability under ambient conditions and demonstrated no significant changes in the visual appearance. However, an increase in the moisture content was exhibited by the film, and the hydrophobic properties was retained until nine months of the storage period. The study of the films antimicrobial activities against Staphylococcus aureus (SA), and Bacillus subtilis (BS) indicated improved resistance to bacterial activities after the incorporation of neem leaves extract and gamma irradiation. The fabricated irradiated seaweed-neem bio-composite film could be used as an excellent sustainable packaging material due to its effective storage stability.

Bionanocarbon Functional Material Characterisation and Enhancement Properties in Nonwoven Kenaf Fibre Nanocomposites.

Bionanocarbon as a properties enhancement material in fibre reinforced nanobiocomposite was investigated for sustainable material applications. Currently, an extensive study using the micro size of biocarbon as filler or reinforcement materials has been done. However, poor fibre-matrix interface results in poor mechanical, physical, and thermal properties of the composite. Hence in this study, the nanoparticle of biocarbon was synthesised and applied as a functional material and properties enhancement in composite material. The bionanocarbon was prepared from an oil palm shell, an agriculture waste precursor, via a single-step activation technique. The nanocarbon filler loading was varied from 0, 1, 3, and 5% as nanoparticle properties enhancement in nonwoven kenaf fibre reinforcement in vinyl ester composite using resin transfer moulding technique. The functional properties were evaluated using TEM, particle size, zeta potential, and energy dispersion X-ray (EDX) elemental analysis. While the composite properties enhancement was evaluated using physical, mechanical, morphological, thermal, and wettability properties. The result indicated excellent nanofiller enhancement of fibre-matrix bonding that significantly improved the physical, mechanical, and thermal properties of the bionanocomposite. The SEM morphology study confirmed the uniform dispersion of the nanoparticle enhanced the fibre-matrix interaction. In this present work, the functional properties of bionanocarbon from oil palm shells (oil palm industrial waste) was incorporated in nanaobiocomposite, which significantly enhance its properties. The optimum enhancement of the bionanocomposite functional properties was obtained at 3% bionanocarbon loading. The improvement can be attributed to homogeneity and improved interfacial interaction between nanoparticles, kenaf fibre, and matrix.

Extracted Compounds from Neem Leaves as Antimicrobial Agent on the Physico-Chemical Properties of Seaweed-Based Biopolymer Films.

Neem leaves extract was incorporated into the matrix of seaweed biopolymer, and the seaweed-neem biocomposite films were irradiated with various doses of gamma irradiation (0.5, 1.5, 2.5, 3.5, and 4.5 kGy). The physical, barrier, antimicrobial, and mechanical properties of the films were studied. The incorporation of 5% w/w neem leaves extract into a seaweed-based film, and gamma irradiation dose of 2.5 kGy was most effective for improved properties of the film. The results showed that the interfacial interaction of the seaweed-neem improved with physical changes in colour and opacity. The water solubility, moisture content, and water vapour permeability and biodegradability rate of the film reduced. The contact angle values increased, which was interpreted as improved hydrophobicity. The tensile strength and modulus of the films increased, while the elongation of the composite films decreased compared to the control film. The film's antimicrobial activities against bacteria were improved. Thus, neem leaves extract in combination with the application of gamma irradiation enhanced the performance properties of the film that has potential as packaging material.

Cytomegalovirus Retinitis during Maintenance Therapy in child with Acute Lymphoblastic Leukemia.

We report three cases of acute lymphoblastic leukemia (ALL) those were suffered from cytomegalovirus retinitis (CMVR) during maintenance phase therapy. Ophthalmologic examination for loss of vision prompted diagnosis of cytomegalovirus retinitis. Administration of anticytomegalovirus drugs led to complete regression of active retinitis. CMVR should be in mind for children with ALL on maintenance of medical aid, even in those without hematopoietic stem cell transplantation state.

Removal of phenol from aqueous solutions by adsorption onto activated carbon prepared from biomass material.

Activated carbon derived from rattan sawdust (ACR) was evaluated for its ability to remove phenol from an aqueous solution in a batch process. Equilibrium studies were conducted in the range of 25-200mg/L initial phenol concentrations, 3-10 solution pH and at temperature of 30 degrees C. The experimental data were analyzed by the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models. Equilibrium data fitted well to the Langmuir model with a maximum adsorption capacity of 149.25mg/g. The dimensionless separation factor RL revealed the favorable nature of the isotherm of the phenol-activated carbon system. The pseudo-second-order kinetic model best described the adsorption process. The results proved that the prepared activated carbon was an effective adsorbent for removal of phenol from aqueous solution.

Abandonment and Outcome of Childhood Acute Myeloid Leukemia in A Tertiary Level Hospital.

Acute leukemias are the most common child hood malignancy, of which acute myeloid leukemia (AML) are 15 to 20%. Abandonment is one of the most important causes of treatment failure in AML in developing countries. Lost to follow-up is also a big problem in low income countries. Many patients stop therapy soon after diagnosis due to cost, distance and ignorance. To determine the abandonment, outcome and treatment related mortality (TRM) and morbidity among children with AML. This prospective observational study was conducted in the Department of Pediatric hematology and Oncology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka from February 2013 to January 2014. Fifty (50) patients of AML visited to out patient department (OPD) of Pediatric hematology and Oncology. Among them 11(22%) patients refuse treatment from outdoor. Thirty nine (78%) patients of AML were selected as per inclusion and exclusion criteria. After proper evaluation and clinical examination of these patients, CBC and Bone marrow examination was done for confirmation of diagnosis. A total of 39 patients were recruited in this study. Seventeen (43.6%) patients were male and 22(56.4%) were female. Mean±SD of age was 7.80±4.42 years and range was 1 year to 18 years. Out of 39 patients, 18(46.1%) patients were abandoned, 15(38.4%) expire, relapse 2(5.2%) & alive 4(10.3%). High abandonment (46.1%) and treatment related toxic death (38.4%) has compromised the outcome of acute myeloid leukemia. However AML can be treated with better outcome if improved the supportive care, reduce toxic death, refusal or abandonment.

Nanosuspension as an ophthalmic delivery system for certain glucocorticoid drugs.

Poorly-water-soluble compounds are difficult to develop as drug products using conventional formulation techniques. The use of nanotechnology to formulate poorly-water-soluble drugs as nanosuspensions offers the opportunity to address many of the deficiencies associated with this class of molecules. In the present study, the high pressure homogenization method used to prepare nanosuspensions of three practically insoluble glucocorticoid drugs; hydrocortisone, prednisolone and dexamethasone. The effect of particle size in the micron and nano-size ranges as well as the effect of viscosity of the nanosuspension on the ocular bioavailability was studied by measuring the intraocular pressure of normotensive Albino rabbits using shiØetz tonometer. The results show that compared to solution and micro-crystalline suspensions it is a common feature of the three drugs that the nanosuspensions always enhance the rate and extent of ophthalmic drug absorption as well as the intensity of drug action. In the majority of cases nanosuspensions extend the duration of drug effect to a significant extent. The data presented confirms that nanosuspensions differ from micro-crystalline suspensions and solution as ophthalmic drug delivery systems and that the differences are statistically, highly to very highly significant. The results confirm also the importance of viscosity of nanosuspension especially in increasing the duration of drug action.

Production of effective luteinizing hormone antisera by two immunization methods.

This paper addresses the production of effective luteinizing hormone antisera by two different immunization methods; the traditional and modified methods. The main difference between these two methods is in the immunization procedure. In the modified method, an additional injection of emulsion with complete Freund's adjuvant and only one booster are applied at the third and 28th day from the first injection, respectively. The results of the study indicated the possibility of producing the antiseria using the modified method in short time and better quality than those produced by the traditional methods. The details of both methods are presented together with the results obtained from the antibodies detection. Comparison between these two methods is also presented along with discussions.

Clinical evaluation of novel buccoadhesive film containing ketorolac in dental and post-oral surgery pain management.

Ketorolac tromethamine (KT), a non-steroidal anti-inflammatory drug, was formulated in buccoadhesive film to overcome the limitations in the currently available routes of administration which in sequence will increase patients' compliance. The film was formulated using aqueous solvents by means of two bioadhesive polymers namely: hydroxylpropyl methyl cellulose (HPMC) and Carbopol 934. The prepared film was subjected to investigations for its physical and mechanical properties, swelling behavior, in vitro bioadhesion, and in vitro, in situ and in vivo release. Anti-inflammatory efficacy and analgesic activity of the prepared buccoadhesive film were investigated in rats using the hind-paw oedema test and the hot plate method. The analgesic efficacy and tolerability of a single 30 mg dose of KT formulated into the buccoadhesive film was clinically evaluated using a standard, widely accepted post-oral surgery pain model. In this study, the prepared film has been administrated to dental post-operative patients for relieving pain in dental hospital clinic. Results indicate that the concentration of KT in the oral cavity was maintained above 4.0 microg/ml for a period of at least 6 h. The buccal KT film was excellently tolerated in all patients and no complains of GI side effects were reported. It is concluded from this clinical evaluation that KT formulated into a buccoadhesive film is effective as a potent analgesic in dental and postoperative oral surgery in a single dose of 30 mg with minimal GI side effects.

Role of adenosine A2A receptor in cerebral ischemia reperfusion injury: Signaling to phosphorylated extracellular signal-regulated protein kinase (pERK1/2).

Following brain ischemia reperfusion (IR), the dramatic increase in adenosine activates A2AR to induce further neuronal damage. Noteworthy, A2A antagonists have proven efficacious in halting IR injury, however, the detailed downstream signaling remains elusive. To this end, the present study aimed to investigate the possible involvement of phospho-extracellular signal-regulated kinase (pERK1/2) pathway in mediating protection afforded by the central A2A blockade. Male Wistar rats (250-270 g) subjected to bilateral carotid occlusion for 45 min followed by a 24-h reperfusion period showed increased infarct size corroborating histopathological damage, memory impairment and motor incoordination as well as increased locomotor activity. Those events were mitigated by the unilateral intrahippocampal administration of the selective A2A antagonist SCH58261 via a decrease in pERK1/2 downstream from diacyl glycerol (DAG) signaling. Consequent to pERK1/2 inhibition, reduced hippocampal microglial activation, glial tumor necrosis factor-alpha (TNF-α) and brain-derived neurotropic factor (BDNF) expression, glutamate (Glu), inducible nitric oxide synthase (iNOS) and thiobarbituric acid reactive substances (TBARS) were evident in animals receiving SCH58261. Additionally, the anti-inflammatory cytokine interleukin-10 (IL-10) increased following nuclear factor (erythroid-derived 2)-like 2 (Nrf-2). Taken all together, these events suppressed apoptotic pathways via a reduction in cytochrome c (Cyt. c) as well as caspase-3 supporting a crucial role for pERK1/2 inhibition in consequent reduction of inflammatory and excitotoxic cascades as well as correction of the redox imbalance.

Layered transition metal dichalcogenides: promising near-lattice-matched substrates for GaN growth.

Most III-nitride semiconductors are grown on non-lattice-matched substrates like sapphire or silicon due to the extreme difficulty of obtaining a native GaN substrate. We show that several layered transition-metal dichalcogenides are closely lattice-matched to GaN and report the growth of GaN on a range of such layered materials. We report detailed studies of the growth of GaN on mechanically-exfoliated flakes WS2 and MoS2 by metalorganic vapour phase epitaxy. Structural and optical characterization show that strain-free, single-crystal islands of GaN are obtained on the underlying chalcogenide flakes. We obtain strong near-band-edge emission from these layers, and analyse their temperature-dependent photoluminescence properties. We also report a proof-of-concept demonstration of large-area growth of GaN on CVD MoS2. Our results show that the transition-metal dichalcogenides can serve as novel near-lattice-matched substrates for nitride growth.

Alcohol abolishes the hypotensive effect of clonidine in spontaneously hypertensive rats.

This study tested the hypothesis that concurrent ethanol administration attenuates the hypotensive effect of clonidine. Four groups of spontaneously hypertensive rats matched for baseline systolic pressure and body weight were randomly assigned the following treatments: (1) water (control), (2) ethanol, (3) clonidine, and (4) ethanol plus clonidine for 13 weeks. Ethanol was provided in the drinking water as 5% for 1 week, 10% for the next 2 weeks, and 20% from week 4 to 13. Starting from similar baseline systolic blood pressures, the blood pressure of the control group increased 10 to 15 mm Hg over the 13-week treatment period. A similar rise in systolic blood pressure occurred in ethanol-treated rats despite a drastic (40% to 50%, P < .05) reduction in fluid intake. Clonidine (300 micrograms/kg per day) caused a smaller and shorter reduction in fluid intake. The fluid intake of the combined treatment group was similar to that of the ethanol group. Either treatment caused a significant and additive reduction in body weight gain. Treatment-related mortality (20%) occurred only in the combined treatment group by the 12th week. Clonidine elicited a slowly developing hypotensive response (P < .05) that started 2 to 3 weeks after treatment was initiated and lasted throughout the treatment period. Ethanol abolished the hypotensive effect of clonidine and resulted in blood pressure values that were not significantly different from those of the control or the ethanol group. Blood ethanol concentration was similar in the presence or absence of clonidine (5.5 +/- 1.9 versus 6.5 +/- 3 mmol/L).(ABSTRACT TRUNCATED AT 250 WORDS)

Reversal by ethanol of the hypotensive effect of clonidine in conscious spontaneously hypertensive rats.

We studied the acute effect of ethanol on the hypotensive response to clonidine in conscious spontaneously hypertensive rats. When administered during the hypotensive response to clonidine, ethanol not only reversed the response but also caused a slight but significant short-lived pressor effect. The maximal hypotensive effect of graded doses of clonidine was significantly (p less than 0.05) attenuated by a dose of 1 g/kg ethanol, which resulted in a peak blood ethanol concentration of 54.2 +/- 6.3 mg/dl. The data strongly suggest the adverse effect of ethanol on the hypotensive response to clonidine is ethanol mediated and that their antagonistic interaction is both reversible and reproducible because: 1) an equal volume of saline had no effect on the hemodynamic responses to clonidine and 2) crossing over ethanol and saline treatments on days 2 and 3, which allowed longitudinal comparisons, showed that the effect of ethanol was similar both in naive rats (day 1) and in rats that were pre-exposed to ethanol (day 3). Whether this negative effect of ethanol also involves other antihypertensive agents that do not act primarily by a central nervous system mechanism was investigated. The same dose of ethanol had little or no effect on the hypotensive response to hydralazine, suggesting the negative effect of ethanol is selective to centrally acting antihypertensive agents. Although the mechanism by which ethanol reverses the hypotensive effect of clonidine is not known, it is possible that it involves an ethanol-evoked increase in plasma catecholamine levels, which are known to be decreased by clonidine. That ethanol did not reverse the hypotensive effect of hydralazine, which is also known to be associated with increased plasma catecholamine levels, supports this notion. The findings of the present study may explain, at least in part, why regular use of alcohol is associated with an inadequate control of blood pressure in treated hypertensive patients who are regular consumers of alcohol.

Differential alteration of neuronal and cardiovascular responses to adenosine microinjected into the nucleus tractus solitarius of spontaneously hypertensive rats.

We previously reported that adenosine elicited site-dependent neuronal and cardiovascular responses in two subareas of the nucleus tractus solitarius (NTS) of normotensive rats. Pressor and tachycardic responses were obtained from the rostral NTS (adenosine pressor system), and depressor and bradycardic responses were obtained from the caudal NTS (adenosine depressor system). In both areas, adenosine inhibited the firing rate of barosensitive neurons. The present study investigated whether spontaneously hypertensive rats (SHR) exhibit abnormal neuronal and cardiovascular responses mediated by the adenosine pressor and depressor systems within the NTS. Male SHR and Wistar-Kyoto rats (WKY) were anesthesized with urethane and prepared for blood pressure and heart rate recording, stereotaxic microinjection of adenosine into the NTS, and extracellular recording of single-unit neuronal activity of NTS neurons. Chemical identification of the targeted neuronal pool was made by L-glutamate (5 nmol) and confirmed by histology. SHR exhibited significantly higher mean arterial pressure and firing rate of caudal NTS neurons (45.0 +/- 4.5 versus 27.3 +/- 4.7 spikes per 2.5 seconds, P <.05) but similar heart rate and neuronal firing rate of rostral NTS neurons compared with WKY. Adenosine (0.1, 1, and 10 nmol) elicited dose-related neuronal and cardiovascular responses in both strains. However, SHR exhibited differential alterations in both adenosine systems. Compared with WKY, SHR exhibited attenuated pressor, tachycardic, and neuronal responses mediated by the adenosine pressor system and exaggerated depressor, bradycardic, and neuronal responses mediated by the adenosine depressor system. In both strains, the responses elicited by adenosine were virtually abolished by theophylline (10 mg/kg IV), suggesting that these responses were mediated by adenosine receptors in the NTS. Furthermore, the theophylline-evoked increase in blood pressure was twofold higher in SHR (15.0 +/- 1.7 versus 6.9 +/- 1.5 mm Hg, P <.05); larger but nonsignificant increases in heart rate and neuronal firing rate also were evident in SHR compared with WKY. These findings suggest differential alterations in adenosine pressor and depressor systems in the NTS of SHR, which may be implicated in the pathophysiology of this model of hypertension.

Ethanol-induced hypertension involves impairment of baroreceptors.

We studied the effect of 12 weeks of ethanol feeding on arterial blood pressure and baroceptor reflex control of heart rate in Sprague-Dawley and Wistar rats. Baroceptor reflex sensitivity and pressor responsiveness were evaluated by evoking graded rises in mean arterial pressure with increasing doses of phenylephrine and angiotensin II. After 12 weeks of ethanol feeding there was a modest increase in mean arterial pressure with no change in heart rate in both strains. When angiotensin II or phenylephrine was used as the pressor agent, baroreceptor reflex curves (relationships between changes in mean arterial pressure and heart rate) of Wistar rats were shifted upward and had a markedly reduced slope compared with those of control rats, suggesting that impairment of baroreceptor reflex control of heart rate had occurred. This effect was less evident in the Sprague-Dawley rats. Ethanol-fed rats had a higher sympathetic activity, since beta-blockade with propranolol decreased heart rate to a greater degree than that seen in control rats. The pressor response curve of phenylephrine was shifted to the right in control rats challenged with ethanol (0.5 g/kg), implying the presence of alpha-blockade. This shift was not present in ethanol-fed rats, showing that tolerance had developed to this effect of ethanol. These findings show that attenuation of baroreceptor reflex function is associated with ethanol-induced hypertension but do not establish whether this is a cause or an effect of the developed hypertension.