摘要:

The possible role of aldosterone in pinealectomy induced hypertension was studied by using daily spironolactone administration (10 mg/kg orally) from the second postoperative day. induced blood pressure elevation was Pinealectomy partly inhibited and the reduction of serum potassium concentration antagonized by spironolactone. The urine volume was increased but the excretion of sodium and potassium decreased in pinealectomized animals. These changes, too, were prevented by spironolactone administration. In spironolactone treated pinealectomized rats the sodium concentration was slightly increased in both the heart and the arterial wall. The ability of spironolactone to antagonize the pinealectomy induced hypertension and the changes in the electrolyte concentrations in plasma and urine supports our earlier suggestion of an increased aldosterone secretion in this type of hypertension in rats.

ISSN:0031-7012    

DOI:10.1159/000136251

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

The response of sodium urate-induced paw welling in mice to various antimitotic and anti-inflammatory agents was studied. Antimitotics colchicine, vinblastine, vincristine and podophyllotoxin produced a significant suppression of paw swelling at similar dose levels. Desacetamidocolchicine, a more potent antimitotic agent than colchicine, was less active against paw swelling even when given in a 58-fold greater dose than colchicine. Anti-inflammatory agents prednisone and indomethacin inhibited paw swelling but phenylbutazone, even at lethal doses, was inactive in this respect.

ISSN:0031-7012    

DOI:10.1159/000136252

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

The effects of i.v. infusions (duration: 15 min) of 25 µg/kg/min methoxamine hydrochloride, an exclusively α-adrenergic sympathomimetic agent, on blood pressure, tolerance blood flow, and vascular resistance in the pulmonary, systemic and femoral circulations were investigated in anesthetized (glucochloralose-N2O) open chest dogs with artificial respiration. (1) Methoxamine caused a steady and continuous increase in systemic blood pressure, total peripheral- and femoral resistance and a continuous decrease in femoral blood flow throughout the entire duration of the infusion. This is in contrast to the effects of infused norepinephrine which exhibited a similar vasoconstrictive action, but this effect declined despite continuing infusion after the peak response had been reached (= acute tolerance). This difference confirms a theory proposed earlier [23] that acute norepinephrine tolerance is due to an interaction of the β-adrenergic with the vasoconstrictive effects of this catechol-amine. (2) The pulmonary circulatory effects of methoxamine differ essentially from its peripheral hemodynamic action. There was a decrease in pulmonary perfusion pressure due to a decrease in cardiac output, and the pulmonary vascular resistance fell slightly and insignificantly. In contrast, the systemic blood pressure and the total peripheral resistance were markedly increased. It is concluded that the reactivity of the pulmonary blood vessels to the vasoconstrictive property of methoxamine is much smaller than that of the systemic vasculature. (3) In a comparison of the pulmonary circulatory effects of 10 sympathomimetic agents with different ratios of α- to β-adrenergic properties it is pointed out that strong β-receptor stimulants increase the pulmonary perfusion pressure, whilst potent α-receptor stimulants lower it or do not change it. The pulmonary vascular resistance is increased most with those sympathomimetics which seem to possess approximately equally strong α- and β-mimetic properties, whilst during the administration of predominantly α- or β-adrenergic agents only very small changes in pulmonary vascular resistance wer

ISSN:0031-7012    

DOI:10.1159/000136253

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:0031-7012    

DOI:10.1159/000135169

出版商:S. Karger AG    

年代:1962

数据来源: Karger

摘要:

In a prior study, catecholamine levels were persistently higher in the carotid than the femoral artery wall. In the present study, catecholamine contents of various artery walls were determined. Renal arteries averaged the highest content of norepinephrine, femorals the lowest; carotids were midway between. Differences in catecholamine values in various conduit vessels may be assumed to be related to adrenergic innervation of the vascular bed supplied. Exogenous administration of adrenergic transmitter substances may cause undesirable events in vascular beds in which physiologic release of catecholamines has been stimulated.

ISSN:0031-7012    

DOI:10.1159/000136254

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:0031-7012    

DOI:10.1159/000135170

出版商:S. Karger AG    

年代:1962

数据来源: Karger

摘要:

This paper describes in detail a relatively simple, versatile technique for the isolation and long-term perfusion of dog and monkey hearts. Hearts perfused at constant flow with autologous heparinized blood remain stable for up to 8 h, while those hearts perfused with oxygenated Locke-Ringer’s solution are viable for approximately 3 h. No significant change in pO2, pCO2, pH and oxygen content of the blood or Locke-Ringer’s solution was observed during these respective periods of perfusion. Methods for the recording of changes in coronary vascular resistance, force of contraction, electrical activity of the myocardium (ECG) and heart rate are shown. Epinephrine (1 µg) caused a brief increase and ellipticine (12.5 mg) a prolonged increase in force of contraction and heart rate. Daunomycin (50 mg) caused a change in the tone of the coronary arteries as indicated by an increase in pump perfusion pressure. The ability of the heart preparation to respond to these 3 agents indicates the possibility of differentiating the way in which substances may alter cardiac func

ISSN:0031-7012    

DOI:10.1159/000136255

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:0031-7012    

DOI:10.1159/000135171

出版商:S. Karger AG    

年代:1962

数据来源: Karger

摘要:

In normal and adrenalectomized rats the potassium-escape-phenomenon during continuous amiloride treatment was studied after pretreatment with diets of different potassium content. (1) The period of potassium retention during amiloride application was shortened when the rats were pretreated with the diet of elevated potassium content. (2) The potassium-escape-phenomenon was not significantly modified in adrenalectomized rats.

ISSN:0031-7012    

DOI:10.1159/000136256

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:0031-7012    

DOI:10.1159/000135172

出版商:S. Karger AG    

年代:1962

数据来源: Karger