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T Lüscher

Publications and source records attributed to T Lüscher.

64 records · Page 4Linked to original sources
PubMed1981

Twenty-four-hour secretory pattern of cortisol in the bull: evidence of episodic secretion and circadian rhythm.

A single antibody RIA method for measurement of plasma cortisol concentrations in the bull is described. Antisera were obtained from rabbits immunized against cortisol-3-oxime-bovine serum albumin. By this technique, peripheral cortisol levels were determined in seven adult bulls (one blind) during 24- and 48-h periods, with blood collections every 30 min. Statistical evaluation of the 24-h profiles using time series analysis revealed that cortisol is secreted episodically throughout the day-night cycle (range, 0.4-9.7 ng/ml). Despite individual variability in both frequency and amplitude of secretory episodes, a distinct circadian secretion pattern was recognized. After dividing the 24 h into three 8-h time periods (I, 0900-1700 h; II, 1700-0100 h; III, 0100-0900 h), a depressed secretory activity with small episodic bursts not exceeding 3.5 ng/ml plasma consistently occurred during time period II. Increased cortisol secretion with high fluctuating levels was evident during time periods I and III. Maximum cortisol concentrations greater than 8 ng/ml were noticed in the morning at the onset of daylight, whereas lowest values were recorded in the evening when darkness began. Results from this study indicate that there is a temporal correlation between the rhythm of cortisol secretion and the light-dark cycle in the bovine species.

Animals↗
PubMed1980

[Captopril in treatment-resistant hypertension (author's transl)].

26 patients with severe hypertension (10 essential, 9 renal parenchymatous, 7 renovascular) and a mean age of 42 years were treated with the new oral converting enzyme inhibitor captopril (SQ 14225). During the initial phase with a standardized triple therapy (STT) consisting of propranolol (maximum 320 mg/day), hydralazine (maximum 200 mg/day) and hydrochlorothiazide (maximum 100 mg/day) or furosemide (maximum 250 mg/day) mean systolic and diastolic blood pressure values remained almost unchanged (184 +/- 32/111 +/- 17 mm Hg to 179 +/- 34/112 +/- 19 mm Hg), indicating true therapy resistance to conventional antihypertensive therapy. After discontinuing each antihypertensive agent captopril was then titrated from 3 X 25 mg/day to a maximum of 4 X 150 mg/day. Mean systolic and diastolic blood pressure values 2, 4, 8, and 16 weeks after starting captopril were 154/95, 155/97, 149/93 and 143/91 mm Hg. The corresponding mean captopril doses were 242, 280, 325 and 299 mg daily. During captopril medication mean systolic and diastolic blood pressure values were significantly lower (p less than 0.05 to p less than 0.005) than during STT. Throughout the observation period of 16 weeks only 15% of the cases were on monotherapy with captopril whereas 62% needed the addition of a diuretic (hydrochlorothiazide or furosemide). In 23% of the cases even the combination of captopril and diuretic was insufficient and thus propranolol was added as a third drug. The side effects observed were 1 case with renal water and fluid retention and with reversible skin rash and 1 with pruritus. The results demonstrate that captopril has good blood pressure lowering activity in patients with treatment-resistant hypertension. However, in the majority of our cases the addition of a diuretic was necessary. Finally, some patients required a beta-blocker as a third drug.

Adult↗
PubMed1980

[Electrolyte balance in arterial hypertension (continuation)].

In patients with arterial hypertension as most frequent disturbance of the electrolyte balance a hypopotassaemia is observed. Examinations of our working team on 517 patients with hypertension exhibited a prevalence of the hypopotassaemia of 3%, in which case in the greater part of these patients (1.6%) a decrease of the serum potassium levels induced by diuretics was present. In the other patients in 1.2% of the cases a secondary and only in 0.2% of the patients a primary aldosteronism was diagnosed as underlying cause. The leading clinical symptom of the primary aldosteronism is a hypopotassaemic hypertension. The diagnosis of the disease is ascertained by the proof of a pathologically increased plasma aldosterone concentration and of a decreased and non-measurable renin activity, respectively. Since these peripheral hormone values do not allow a differential diagnosis between an adenoma producing aldosterone and an idiopathic hyperplasis of the adrenal cortex, further investigations for the differentiation of these two main forms of the primary aldosteronism must be performed. These investigations are: Phlebography of the suprarenal bodies, determination of the aldosterone concentration in the blood of the adrenal veins and iodine-131-cholesterol scintigraphy. Patients with an adenoma producing aldosterone are unilaterally adrenalectomized, while an operative intervention has no essential influence of the behaviour of the blood pressure in cases with idiopathic hyperplasia of the adrenal cortex. Therefore, these cases must be treated antihypertensively. A pseudo-primary aldosteronism, also shows a hypopotassaemic hypertension as leading symptom. In contrast to the genuine primary aldosteronism this disease, differs by the proof of low plasma aldosterone levels. A pseudo-primary aldosteronism is caused by the exogenic supply of mineralocorticoid-effective substances. A hypopotassaemia in patients with Cushing's syndrome should, above all when it is very expressed, attract the suspicion to a cortisol-producing carcinoma of the adrenal cortex. The hypopotassaemia in these patients is caused by additional abnormally high tumour production of mineralocorticoid-effective steroids.

Adrenal Cortex Neoplasms↗
PubMed1979

[Hypertension in unilateral (non-vascular) nephrosclerosis: renin activity in the venous kidney blood and effect of nephrectomy].

13 patients (9 females, 4 males) with hypertension and unilateral (non-vascular) small kidney underwent nephrectomy. Before surgery, renin activity (PRA) was measured in renal vein blood before and/or 15 and 30 minutes after intravenous stimulation with 40 mg furosemide. From these PRA values renin rations (PRA affected side/PRA unaffected side) were calculated. A ratio of greater than or equal to 1.5 was considered to be significant. After a mean postoperative observation period of 3.9 +/- 1.3 years 6 patients (46%) were cured and 6 were improved. In only 1 patient (8%) did hypertension remain unchanged. No differences could be observed between the renin ratios of cured and improved cases. Furthermore, in no patient was a correlation found between preoperative renin ratios and the degree of postoperative blood pressure reduction. Finally, both patients with renin ratios less than or equal to 1.4 were cured by surgery. Marked differences between cured and improved patients were seen in preoperative blood pressure values, age, duration of hypertension and renal function. Cured patients were younger and had much lower mean systolic and diastolic blood pressure values, shorter duration of hypertension and better renal function than improved patients. These results show that the diagnostic and prognostic validity of renal venous renin ratios is very limited in patients with a unilateral (non-vascular) small kidney. In these patients the effect of nephrectomy can already be predicted by analyzing simple anamnestic, clinical and chemical data.

Adolescent↗
PubMedDate not supplied

Endothelin in cardiovascular control: the role of endothelin antagonists.

Endothelin (ET) is a potent vasoconstrictor associated with various cardiovascular diseases. ET mediates its effects through ET receptors on vascular smooth muscle cells as well as on the vascular endothelium. Furthermore, a neurotransmitter role for ET has been suggested on the basis of experimental and human in vivo studies. ET antagonists are potent tools for studying the effects of ET and its receptors. They have been widely used in vitro and in experimental models of cardiovascular disease, where ET levels are elevated and reactivity to ET is altered. Promising clinical trials in hypertension, coronary artery disease, and congestive heart failure are discussed in this review. Different forms of renal failure are associated with markedly increased ET levels, and ET antagonists experimentally improve renal function in these models. Extrapolating from experimental and first clinical experience, ET antagonists could be useful in the treatment of hypertension, coronary artery disease, congestive heart failure, and renal failure, especially in combination with other drugs, ie, angiotensin converting enzyme inhibitors. The inhibition of ET-induced stimulation of nociception allows for speculation that ET antagonists might even have analgesic properties.

Animals↗