摘要:

SUMMARY1 The dose of thyroxine (0‐150 μg/kg body weight) administered subcutaneously daily to surgically thyroidectomized male rats was correlated significantly with their metabolic activity as assessed by rate of oxygen consumption and colonic temperature.2 There was a significant dose‐dependent increase in total serum thyroxine, triiodothyronine and reverse‐triiodothyronine concentrations with increasing doses of thyroxine administered.3 The cardiostimulatory response to administration of isoprenaline (8 μg/kg body weight s.c.) was also correlated directly with the dose of thyroxine administered.4 The concentration of cardiac β‐adrenoceptors in these animals was correlated significantly with total serum thyroxine and triiodothyronine concentrations, basal heart rate, and the chronotropic response to administration of is

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1983.tb00176.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SUMMARY1. Cerebral blood flow (CBF) and cerebral O2metabolism (CMRO2) changes were measured in these studies during treatment with three reputed cerebral vasodilators: bradykinin, adenosine triphosphate (ATP) and increased arterialPco2.2. Intracerebrovascular bradykinin infusions increased CMRO2and CBF to a similar degree. Intramaxillary ATP infusions increased CBF to an extent greater than that required for increases seen in CMRO2. Hypercapnia increased CBF without a significant change in CMRO2.3. Results suggest that increases in cerebral metabolism may mediate most, some and none of the cerebrovascular changes produced by bradykinin, ATP or hypercapnia, respectively.

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1983.tb00177.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SUMMARY1. Intracerebroventricular (i.c.v.) administration of morphine produced dose‐dependent behavioural changes in rats, the highest dose producing violent tonic convulsions.2. Naloxone (up to 10 mg/kg i.p., or 100 μg i.c.v.) failed to reverse morphine‐induced toxicity.3. The conventional anticonvulsant drugs also failed to offer protection to morphine‐induced seizures.4. GABA‐ergic substances, GABA, piracetam and diazepam, on the other hand, protected the animals against morphine‐induced convulsions and toxicity. Similarly, clonidine pretreatment also had a protective action against morphine‐induced

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1983.tb00178.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SUMMARYThis study was designed to compare the activity of three structurally different drugs (SQ 14 225, SA 446, and MK 421) as inhibitors of angiotensin converting enzymein vivoand to compare their effects in two experimental models of hypertension.2 MK 421 was less effective than SA 446 or SQ 14 225 in suppressing the pressor responses to intravenous angiotensin I 3 min after the administration of low doses of the converting enzyme inhibitors (CEIs) but more effective than SA 446 or SQ 14 225 30 min or longer after doses of CEIs ranging from 25 to 2500 nmol/kg i.v.3 The CEIs administered at 8 μmol/kg intravenously blocked the pressor response to angiotensin I (AI) to a similar maximal effect but the time for recovery was much slower for MK 421 than for SQ 14 225 or SA 446. After oral administration (15 mg/kg) prolonged blockade was observed with each of the three drugs although some recovery occurred with SA 446 after 5 h. The effect of a small dose of MK 421 intravenously (0.4 μmol/kg) was more prolonged in anaesthetized than in conscious spontaneously hypertensive rats (SHR).4 Anaesthetized adult SHR showed slow progressive falls of blood pressure after 8 /unol/kg of each drug intravenously although the effect of SA 446 was less than for SQ 14 225 or MK 421 which were equipotent. After acute oral administration of each CEI at 80 μmol/kg, conscious SHR showed significant falls in blood pressure but the effect of SA 446 was less than the other two inhibitors which appeared equipotent.6 After chronic oral administration of the drugs to conscious SHR, SA 446 (80 μmol/kg per day) did not alter blood pressure although SQ 14 225 was effective at this dose. At a higher dose of 160 /μmol/kg per day SA 446 significantly lowered blood pressure of SHR in a manner similar to the same dose of SQ 14 225 or MK 421.7. We conclude that the three drugs are potent, orally effective converting enzyme inhibitors. The duration of action was in the order MK 421>SQ 14 225>SA 446. MK 421 appears the most potent due to both a higher affinity for converting enzymein vitroand a longer persistence of actionin vivo.In renal hypertension, the drugs appeared equipotent but in the SHR at low doses, SA 446 was ineffec

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1983.tb00179.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SUMMARYInflammation was induced in the hind legs of rats by formalin injection and thein vitrojejunal absorption of14C‐glucose was studied.Treatment of rats with formalin caused a reduction in thein vitroabsorption of glucose from the jejunum.Oral administration of oxyphenbutazone or a herbal anti‐inflammatory drug (Withania somnifera)prior to formalin injection, resulted in no alteration in the jejunal absorption of gluc

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1983.tb00180.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SUMMARYThe collecting ducts in papillae taken from normal rats have a measurable increase in diffusional tritiated water (THO) permeability with ADH 5 μunit/ml and this increase is maximal with antidiuretic hormone (ADH) 100 μunit/ml added to the media.2 The presence of plasma from rats pretreated with lithium to make them polyuric inhibited the response to ADH. The lowest concentration of ADH that caused a measurable increase in diffusional water permeability was 50 μunit/ml and the increase was maximal with ADH 2000 μunit/ml.3 The maximum response to ADH did not differ whether plasma from control or lithium pretreated rats was used. However, the dose‐response curve to ADH was shifted to the right by the plasma from lithium‐pretreated rats.4 Lithium added to the plasma from control rats did not alter the response to ADH.5 It is proposed that lithium given to rats causes a circulatory factor to be produced that inhibits in a competitive fashion the response of the collecting duct to ADH. Such an effect would explain many features of the impairment of water excretion associated with lith

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1983.tb00181.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SUMMARY1. Ischaemic pain onset and tolerance in response to a pneumatic blood pressure cuff were compared in 17 non‐deprived smokers, 30 deprived smokers, 15 smokers chewing nicotine gum and 16 non‐smokers.2. Following removal of the cuff, all subjects completed the McGill pain questionnaire, rating pain in terms of its sensory, affective, evaluative and miscellaneous qualities.3. Group differences were found in the time elapsing before reporting the first twinge of pain. Non‐deprived smokers had the shortest period to onset of pain. The longer the smokers had been deprived of cigarettes, the longer before the onset of pain.4. Non‐deprived smokers also had a significantly shorter period of pain tolerance compared to deprived smokers.5. Non‐deprived smokers tended to have a faster pain onset and a shorter tolerance period compared to non‐smokers.6. Smokers’ indices of pain were significantly higher on the several sub‐scales describing the qualitative pain experience compared to non‐smokers and to smokers deprived of cigarettes for more than one hour.7. Deprivation of cigarettes appears to diminish smokers’ sensitivity to pain significantly below that of non‐smokers and smoking cigarettes tends to heighten sensitivity to, or beyond, the

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1983.tb00182.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SUMMARYIndomethacin (2.8 μmol/1) did not consistently affect basal tone of sheep coronary artery strips, while a ten‐fold higher concentration increased tension in 50% of the preparations tested. When acetylcholine was used as a spasmogen, oscillations in induced tone and relaxations produced by arachidonic acid (6.6 μmol/1) were abolished by indomethacin, 2.8 μmol/1 and 7 μmol/1, respectively.Prostacyclin (PGI2) and prostaglandin E1decreased and PGE2increased arterial tension while PGF2αwas inactive. Responses to PGI2were reduced by indomethacin (28 μmol/1) but not by indomethacin (2.8 μmol/1).It is suggested that sheep isolated coronary arteries synthesize and release prostacyclin in the presence of acetylcholine and arachidonic acid and that such synthesis can be inhibited by indo

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1983.tb00183.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

SUMMARYPhenylephrine (1 μg/min) was infused into the renal artery of pentobarbitone anaesthetized dogs. Systemic blood pressure and renal blood flow were monitored. Arterial and renal venous blood samples were collected before and 10 min after the start of the infusion. Plasma prostaglandin E2concentration and plasma renin activity were measured by radioimmunoassay.This dose of phenylephrine did not affect systemic blood pressure and renal blood flow.However, both prostaglandin E2and renin secretion rates were increased by the infusion of phenylephrine.These results suggest that renal α‐adrenoceptors participate in prostaglandin and renin release independent of the changes in systemic blood pressure and renal blood f

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1983.tb00184.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

ISSN:0305-1870    

DOI:10.1111/j.1440-1681.1983.tb00185.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY