摘要:

SUMMARY1. Plasma levels of β‐thromboglobulin, initial and total platelet aggregation (induced by adrenaline or adenosine diphosphate [ADP]) were determined in 26 normotensive subjects and 26 patients with untreated essential hypertension. Groups of 18 essential hypertensive patients and 18 age‐ and sex‐matched normotensives were compared.2. After 7 days of treatment with prazosin in a dose of 2–8 mg daily the above measures were repeated in 18 essential hypertensive patients. A significant increase in plasma levels of β‐thromboglobulin, initial and total adrenaline‐induced as well as ADP‐induced platelet aggregation was found in hypertensives. Prazosin restored the mean arterial blood pressure in hypertensives to normal, but it had no significant influence either on increased β‐thromboglobulin levels or on initial and total aggregability.3. The results confirm increased platelet aggregation andin vivoplatelet activation in patients with essential hypertension; however there is a discrepancy with previous reports about those results obtained after prazosin therapy. The results suggest that increased platelet aggregation andin vivoactivation need not be restored to normal after effective antihypertensive therapy alone. They give reason for the combination of antihypertensive together with anti‐aggregatory therapy in es

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1990.tb01284.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

SUMMARY1. Ethamsylate (diethylammonium 2,5‐dihydroxybenzene sulfonate, DicyneneTM), a systemic haemostatic agent with an unknown mechanism of action, was tested for anti‐inflammatory activity using the carrageenan‐induced rat paw oedema test.2. Ethamsylate was shown to be an effective anti‐inflammatory agent with a time course and amplitude of effect similar to that of indomethacin, although the potency was only about 4% of that for indomethacin.3. When ethamsylate and indomethacin were co‐administered they did not show additive effects, suggesting that they do not share a common mode of action. It is proposed that ethamsylate, like indomethacin, may inhibit prostaglandin

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1990.tb01285.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

SUMMARY1. Experimental determinations of blood‐brain barrier permeability from measurements of uptake of tracers by brain are limited in two ways. First, there are experimental limitations that are specific to the particular method being used. These limitations include the range of permeability values that a particular method can reliably determine (sensitivity); whether repeated experiments are possible in the same animal; whether regional values can be determined; and to what degree the chemical composition of the perfusate passing through the brain can be controlled.2. A second set of limitations on permeability determinations is of a more general, physiological nature. These constraints apply to a greater or lesser degree to all experimental determinations, and may limit the accuracy and reliability of the permeability values obtained; although certain reliable upper and lower bounds can be determined. These general factors include: capillary heterogeneity (i.e. variations in capillary lengths, surface areas, blood flows, etc.); the possibility of binding to circulating plasma proteins, especially albumin; and the possibility of capillary recruitment and de‐recruitment with changes in cerebral blood f

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1990.tb01286.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

SUMMARY1. The effects of corticosteroid pretreatment on acetylcholine (ACH)‐induced contraction of bronchial smooth muscle (BSM) were studied.2. ACH dose‐response curves for dexamethasone (DM)‐ and corticosterone (B)‐treated but not deoxycorticosterone (DOC)‐treated BSM were significantly shifted to the right; this provides evidence that glucocorticoid treatment reduced the sensitivity of BSM to ACH.3. Morphine enhanced BSM contraction in response to ACH by 20%. DM suppressed this enhancement.4. These findings correlated well with the reduction of muscarinic receptor numbers in BSM by glucocorticoids in our previous study. In addition, glucocorticoids reduced the sensitivity of BSM t

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1990.tb01287.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

SUMMARY1. We investigated effects of theophylline (widely used for the treatment of asthma) and enprofylline (a new xanthine derivative with negligible adenosine antagonism) on O2‐production by human neutrophils withn‐formyl‐methionylleucyl‐phenylalanine (FMLP) stimulation.2. Therapeutic concentrations of theophylline (1–100 μmol/L) enhanced O2‐production, maximally by 43.1 ± 24.4% at 30 μmol/L; the same concentrations of enprofylline inhibited O2‐production.3. When each agent was administered after pre‐incubation with adenosine deaminase (ADA) (0.1 U/mL), O2‐production was inhibited in a concentration‐dependent manner in comparison with that under administration of ADA alone.4. These results suggest that the difference of effects in the two xanthine derivatives at therapeutic concentrations might be due to the presence or absence o

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1990.tb01288.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

SUMMARY1. The effect of two doses of endothelin, 10 and 50 ng/kg per min, i.v., on glomerular filtration rate (GFR), tubular stop flow pressure and pre‐ and postglomerular vascular resistance have been studied in anaesthetized rabbits.2. Blood pressure did not change significantly in response to 10 ng/kg per min endothelin or vehicle infusion, but rose steadily during infusion of 50 ng/kg per min endothelin, increasing 11.8±2.7 mmHg by 90 min of infusion.3. Glomerular filtration fraction (3H‐inulin extraction ratio) rose and remained elevated throughout the endothelin infusion at 50 ng/kg per min. GFR did not change significantly until 70–90 min of the infusion (50 ng/kg per min) when it decreased by about 35%. No significant changes were seen at 10 ng/kg per min endothelin.4. Sodium excretion rate rose in response to the lower dose, due to an increase in fractional sodium excretion. No changes in sodium excretion were seen at the higher dose of endothelin.5. Glomerular capillary pressure rose significantly in response to endothelin infusion (50 ng/kg per min).6. Renal blood flow fell progressively in response to endothelin (50 ng/kg per min), to about one‐third of the pre‐infusion value.7. Renal vascular resistance increased progressively with both doses of endothelin, by about 35% at 10 ng/kg per min and about 400% at 50 ng/kg per min after 70–90 min. Preglomerular resistance increased from 1.0±0.1 to 5.0±1.9 mmHg/mL per min in response to endothelin 50 ng/kg per min. Postglomerular resistance rose from 1.0±0.1 to 5.6±2.17 mmHg/mL per min.8. Thus endothelin infusion caused progressive renal vasoconstriction with similar magnitude increases in both pre‐ and postglomerular vessels. The vasoconstriction of the kidney caused by endothelin occurred at a dose which did not effect syste

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1990.tb01289.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY

摘要:

Diet and Drug Interactions, 2nd edn By Daphne A. Roe.Health, Safety and Environmental Control.By Reynold L. Hoover, Robert C. Hancock, Kevin L. Hylton, O. Bruce Dickeson and George E. Harris.

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1990.tb01290.x

出版商:Blackwell Publishing Ltd    

年代:1990

数据来源: WILEY