Effects of arachidonate metabolism inhibitors on basal and human chorionic gonadotropin-stimulated progesterone secretion by rat corpus luteum cells in vitro.
Forty-one men over the age of 50 years with an American Urological Association (AUA) symptom score greater than 8, postvoid residual urine volume (PVR) less than 300 mL, and no clinical or biochemical evidence of prostate cancer were treated with terazosin independent of the baseline PFR. The effect of terazosin on the AUA symptom score and PFR were compared for subjects with a PFR of 15 mL/s or less (group I) and those with a PFR greater than 15 mL/s (group II).
Transient growth signals which can be related to protein synthesis and cellular growth are of particular interest in the heart because of the incidence of cardiac hypertrophy in man. The isolated coronary perfused adult rat heart or the so-called Langendorff preparation, is an useful model in exploring not only protein synthesis but also c-fos/c-myc protooncogene and Heat Shock Protein (HSP) gene expression. Phenylephrine infusion in this preparation induces c-fos expression whether the heart is beating or reversibly or irreversibly arrested by solutions enriched in KCl. Norepinephrine has the same effect. Quantitative analysis with slot blots shows that in both cases the adrenergic effect has a dual origin since it is inhibited both by propranolol, a beta-adrenergic antagonist, and terazosine, a soluble alpha 1-adrenergic antagonist. We conclude that the isolated heart is a useful tool to explore the early changes in gene expression which occur in this tissue in response to various physiological stimuli.
We prospectively studied the effect of terazosin on bladder compliance in 12 spinal cord injured patients. All study patients had demonstrated previously poor compliance despite clean intermittent catheterization and maximum anticholinergic therapy. Patients were started on 5 mg. terazosin nightly for 4 weeks. They were evaluated with a history, physical examination, symptom score, and synchronous cystoscopy and cystometry before, during and after terazosin therapy. Detrusor compliance improved in all patients during the treatment phase. The change in bladder pressure and the safe bladder volume were statistically and clinically significant. Patients also reported fewer episodes of incontinence and dysreflexia. The improvement in compliance and continence suggests that in the spinal cord injured patient terazosin may have an effect on alpha receptors in the detrusor muscle or central effects and that improved compliance is not due to decreased outlet resistance.
The treatment related rates of dizziness, asthenia, postural hypotension and syncope were 19%, 6%, 6% and 1%, respectively. Of these adverse events only postural hypotension was associated with orthostatic blood pressure changes. The incidence of asthenia, dizziness and postural hypotension was not significantly greater in patients with a systolic blood pressure decrease of 5 or greater and less than 5 mm. Hg, respectively.
We investigated the contribution of alpha1-adrenoceptor mechanisms to urethral dysfunction associated with diabetes mellitus (DM) in rats.
The ability of the quinazoline derived alpha1-adrenoceptor antagonists doxazosin and terazosin to induce apoptosis in benign and malignant prostate cells has been established. In this study we investigated the effect of the 2 piperazidinyl quinazoline based alpha1-adrenoceptor antagonists and the methoxybenzene sulfonamide alpha1-antagonist tamsulosin on human prostate cancer cell adhesion.
Thirty-five rats were implanted with electroencephalogram and neck electrodes to record sleep-wake states and GG and diaphragm electrodes for respiratory muscle recordings. Microdialysis probes were inserted into the HMN.
To summarize the urinary, rectal, and sexual symptoms occurring during the first 12 months following 125I prostatic implantation.
Trials were eligible if they (1) randomized men with BPH to receive tamsulosin in comparison with placebo, other BPH medications or surgical interventions and (2) included clinical outcomes such as urologic symptom scales, symptoms, or urodynamic measurements, and (3) had a treatment duration of 30 days or longer. Eligibility was assessed by at least two independent observers.
Structural similarities were identified among AT(1) and α(1)-antagonists, initiating a speculation that α(1)-antagonists could possibly block the AT(1) receptor and vice-versa.
The comparative effects of antihypertensive agents, quinazoline or quinazolinedione residues (prazosin, bunazosin, terazosin, SGB-1534, and ketanserin), on the binding of [3H]prazosin, [3H]p-aminoclonidine and [3H]dihydroalprenolol([3H]DHA) to alpha 1-, alpha 2-, and beta-adrenoceptors in the rat brain were examined using radioligand binding assay methods. pA2 values were also obtained in the isolated rat aorta (alpha 1-adrenoceptor) using phenylephrine as an agonist. A strong inhibition by these drugs of [3H]prazosin binding to alpha 1-adrenoceptors was observed, while the inhibition of [3H]DHA binding to beta-adrenoceptors and [3H]p-aminoclonidine binding to alpha 2-adrenoceptor was found to be very weak. The rank order of antagonistic potencies of these drugs against the alpha 1-adrenergic receptors was determined by inhibition constants (Ki) with SGB-1534 = prazosin = bunazosin greater than terazosin greater than ketanserin. The pA2 value of these drugs, in contrast, had prazosin with higher pA2 value than that of SGB-1534. From these two different types of experiments, it was clear that these drugs antagonized alpha 1-adrenoceptors even in the central nervous system, and the side chains bound to quinazoline and quinazolinedione residues may play an important role in the antagonistic potencies for alpha 1-adrenoceptors in the central nervous system as in the peripheral tissues.