Initially a dose-response curve of phenylephrine was constructed at dose strengths of 1-16 microg/kg in a cumulative manner. Phenylephrine caused a significant rise in the mean arterial pressure, left ventricular systolic pressure, left ventricular contractility, stroke volume and a significant decline in the heart rate. Terazosin was administered in three selected doses of 10, 100 and 300 microg/kg. Following each dose of terazosin, dose-response curve of phenylephrine was constructed. Terazosin, per se, decreased the basal mean arterial pressure, left ventricular systolic pressure, left ventricular contractility and stroke volume significantly in a dose dependent manner with an increase in the heart rate with no significant change in the cardiac output. The baroreflex sensitivity at all the three doses remained unchanged. In conclusion, the present findings support the view that terazosin reduces the blood pressure in a physiologically more favorable manner by maintaining the neural integrity of the cardiovascular system.
hytrin 5mg capsules
Women with polycystic ovary syndrome (PCOS) have hyperandrogenemia and increased prevalence of risk factors for cardiovascular disease, including elevated blood pressure. We recently characterized a hyperandrogenemic female rat (HAF) model of PCOS [chronic dihydrotestosterone (DHT) beginning at 4 wk of age] that exhibits similar characteristics as women with PCOS. In the present studies we tested the hypotheses that the elevated blood pressure in HAF rats is mediated in part by sympathetic activation, renal nerves, and melanocortin-4 receptor (MC4R) activation. Adrenergic blockade with terazosin and propranolol or renal denervation reduced mean arterial pressure (MAP by telemetry) in HAF rats but not controls. Hypothalamic MC4R expression was higher in HAF rats than controls, and central nervous system MC4R antagonism with SHU-9119 (1 nmol/h icv) reduced MAP in HAF rats. Taking a genetic approach, MC4R null and wild-type (WT) female rats were treated with DHT or placebo from 5 to 16 wk of age. MC4R null rats were obese and had higher MAP than WT control rats, and while DHT increased MAP in WT controls, DHT failed to further increase MAP in MC4R null rats. These data suggest that increases in MAP with chronic hyperandrogenemia in female rats are due, in part, to activation of the sympathetic nervous system, renal nerves, and MC4R and may provide novel insights into the mechanisms responsible for hypertension in women with hyperandrogenemia such as PCOS.
hytrin maximum dosage
These studies provide no evidence of prostate selectivity for tamsulosin. 0.4 mg tamsulosin is a sub-optimal blocking dose and is equivalent to 1 mg of doxazosin and terazosin (1-2 mg). It is recommended that future comparative studies on benefit/risk in patients should include a range of doses encompassing the ED50.
hytrin 2mg tab
Pheromones in the urine regulate aggression of male mice and castrated males produce less of these pheromones. We tested the hypothesis that pheromones in the urine of sexually mature-intact (SMI) males placed in the cage bedding of an individually housed male mouse or in a mouse restrainer would contribute to a significant increase in mean arterial pressure (MAP), heart rate (HR), and activity. Sexually mature male C57BL/6 mice were implanted with a biotelemetry transmitter to measure MAP, HR, and activity. Urine (200 μL) from SMI mice placed in the cages of singularly housed male mice caused significant changes above baseline values for MAP (21 ± 4 mmHg), HR (145 ±25 bpm), and activity (9 2 counts) when compared to urine from castrated mice-induced MAP (11 ± 3 mmHg), HR (70 ± 15 bpm), and activity (5 ± 1 counts). Pretreatment with terazosin significantly reduced the change in MAP (9 ± 3 mmHg), heart rate (90 ± 15 bpm), and activity (4 ± 2 counts) responses to urine from SMI males. Saline did not significantly increase MAP, HR, or activity in any group. During restraint, urine from SMI mice caused a significant change in MAP (5 ±0.4 mmHg) and HR (17 ±1 bpm); urine from castrated mice did not cause a significant increase in MAP and HR. Our results demonstrate that a significant increase in MAP, HR, and activity occurs when male mice are exposed to urine pheromones from SMI males. In summary, pheromones in the urine of SMI male excreted in the cage bedding and mouse restrainers contribute to a significant increase in cardiovascular responses in the absence of direct physical contact with a different male mouse or animal handler.
IMS and GERS market data of drugs for LUTS suggestive of BPO in France are presented. In addition, data from the THALES database for 1997 and 1998 containing the patient medical records of 620 French GPs were analysed with special emphasis on the initial management by GPs and switch rate to another treatment option.
hytrin with alcohol
To study the effect of nitric oxide donor and alpha(1)-receptor antagonist on proliferation/apoptosis of hyperplastic prostatic stromal cells in vitro.
hytrin 7 mg
Terazosin in a dose of 10 mg/day was well tolerated and effective in reducing bladder outlet obstruction in many spinal cord-injured patients, as reflected by a decrease in maximum detrusor pressure and MUPG in 49% of the patients. Patients with a weak or negative response initially may respond later. Terazosin should be considered a first-line treatment of VSD prior to contemplating surgery.
hytrin dosage forms
Receipt of medical therapy for incident BPH (ie, selective α-1 blockers [prazosin (released 1976), terazosin (1987), doxazosin (1990), tamsulosin (1997), alfuzosin (2003), silodosin (2009)] and 5-ARIs [finasteride (1992) and dutasteride (2002)]).
buy hytrin australia
To investigate the effects of alpha-1 adrenergic blockers on pupil diameter (PD) in rats.
Chronic administration of alpha 1-receptor antagonists is associated with loss of clinical efficacy, especially in congestive heart failure, although the mechanism is uncertain. To evaluate changes in venous alpha 1-adrenoceptor responsiveness during chronic alpha 1-adrenoceptor blockade, dose-response curves to phenylephrine and angiotensin II were constructed in 10 healthy subjects before, during, and after administration of terazosin 1 mg orally for 28 d. Terazosin initially shifted the dose-response curve of phenylephrine to the right, with a significant increase in ED50 for phenylephrine from a control value of 102 to 759 ng/min on day 1 of terazosin (P < 0.001). However, by day 28, the dose-response curve had shifted back towards baseline with an ED50 of 112 ng/min. After discontinuing terazosin, the ED50 for phenylephrine remained near the baseline value, indicating no evidence of supersensitivity to phenylephrine. There was no change in responsiveness to angiotensin II during the course of treatment with terazosin. Plasma terazosin concentrations were stable throughout the period of drug administration. The mean Kd of terazosin was estimated as 11 +/- 15 nM in the first few days of treatment. This study demonstrates that pharmacological tolerance to the alpha 1-adrenoceptor blocking action of terazosin occurs in man and may be responsible for loss in efficacy with chronic therapy.
hytrin generic name
Patients with lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH) often present with voiding and storage symptoms, which may require combination therapy with an alpha blocker and an antimuscarinic (AM). This study compared treatment persistence in LUTS/BPH patients on alpha blocker monotherapy with those using combination alpha blocker and AM therapy (AB/AM).
hytrin 2mg capsules
Prazosin and terazosin are two alpha 1-adrenoceptor blocking agents, their principal difference being the longer half-life of terazosin. The present study was carried out to determine if elderly subjects are different from the young in their pharmacokinetic handling of these two drugs and if age influences the blood pressure response to each drug. Ten young healthy subjects (aged 19-30 years) and five older healthy subjects (aged 54-62 years) received 1 or 2 mg terazosin, 1 or 2 mg prazosin, or placebo 1 week apart according to a 5 X 5 Latin square design. Concentrations of prazosin and terazosin were measured using a high-performance liquid chromatographic procedure with a detection limit of approximately 0.25 ng/ml. Pharmacokinetic parameters of prazosin were virtually the same in both groups, whereas mean terazosin plasma concentrations were higher in the older group and pharmacokinetic analysis revealed higher peak plasma concentrations and a longer terminal elimination half-life. There was no evidence of increased sensitivity to the hypotensive action of the drug, as peak upright blood pressure falls were similar in the two groups. Symptoms of dizziness in the upright position were also less common. In view of their lack of sedative effects and minimal metabolic disturbances, further studies should be conducted to assess the suitability of these drugs as monotherapy for hypertension in elderly patients.
An Internet-based decision support tool was developed to help patients with benign prostatic hypertrophy (BPH) determine whether they wanted to use alpha blockers. The Internet site incorporates a meta-analytic model of the results of randomized trials of the alpha blocker terazosin. The site describes alternative treatments for BPH and potential adverse effects of alpha blockers. The site then measures patients' current symptoms and desired level of symptom reduction. In response, the site computes and displays the probability of a patient's achieving his objective by means of terazosin or placebo treatment.
hytrin drug class
Information on patients, interventions, and outcomes were extracted by at least two independent reviewers using a standard form. The main outcome measure for comparing the effectiveness of tamsulosin with placebo, medical or surgical interventions was the change in urologic symptom scale scores. Secondary outcomes included changes in urinary flow measures (peak urine flow rate). The main outcome measure for adverse effects was the number of men reporting adverse effects.
hytrin tablet dosage
A general genitourinary assessment was documented most frequently for patients receiving 5-ARIs and least frequently in patients receiving nonselective alpha-blockers. A digital rectal examination was documented in 11% of patients. Prostate-specific antigen concentrations were assessed evenly across all medication classes and documented in 47% of eligible patients. However, the American Urological Association Symptom Index and quality-of-life questions were not performed on any patients, and assessments of adverse effects were not documented.