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Biomedical subjects

A Simon

Publications and source records attributed to A Simon.

At least 505 records · Page 28Linked to original sources
PubMed1976

Dopamine receptors and dopaminergic nerves in the vas deferens of the rat.

Phentolamine antagonized competitively the effects of noradrenaline (pA2 = 7.1), dopamine (pA2 = 8.0) and tyramine (pA2 = 8.2). Haloperidol had a pA2 value of 7.3 against dopamine and 6.5 against noradrenaline. Apomorphine antagonized competitively dopamine (pA 2 = 4.8) and tyramine (pA2 = 5.1) and noncompetitively antagonized noradrenaline (pD'2 = 3.6). From these data it is concluded that these antagonists interact with dopamine receptors and alpha-adrenergic receptors. Apomorphine (10-4 M) attenuated the maximal response to dopamine and field stimulation, whereas the same concentration of apomorphine potentiated the maximal response to noradrenaline. Assuming that tyramine and field stimulation release the naturally occurring neurohumoral transmitter from adrenergic nerve endings, it is concluded that dopamine is the physiologically functional neurohumoral transmitter in the rat vas deferens which, when released, stimulates specific dopamine receptors.

Animals↗
PubMed1976

The spectrum of pressor-response to norepinephrine in normotensive and hypertensive patients.

The pressor-response to norepinephrine was determined in the whole body circulation of 15 normal subjects and 86 untreated essential hypertensive patients. The slope, the threshold-dose and the critical-dose were calculated from the log dose-response curve. In the overall population (101 subjects) a slight correlation (r = +0.20 less than 0.05) was observed between the basal diastolic arterial pressure and the threshold-dose. In contrast, highly significant parabolic correlations (r = +0.46 less than 0.00001) were observed between the diastolic arterial pressure and the slope or the critical dose. When diastolic arterial pressure was above 100 mmHg, the slope increased while the blood pressure increased. This result suggests either a decreased sympathetic tone or an adaptative structural change of the arterial wall. When diastolic arterial pressure was under 100 mmHg, the slope decreased while the blood pressure increased. This observation points to an enhanced sympathetic activity in mild blood pressure.

Adult↗
PubMed1975

[Paroxysmal ACTH secretion from an adrenal medullary tumour (author's transl)].

A secondary Cushing's syndrome developed in a 38-year-old woman from an ACTH secreting phaeochromocytoma. Large amounts of ACTH were demonstrated in the tumour by radioimmunological tests. A remarkable feature was that clinical and biochemical signs of increased catecholamine secretion completely regressed with time and the adrenals were stimulated at intervals by the ectopic ACTH secretion, steroid excretion falling to normal in between.

Adrenal Gland Neoplasms↗
PubMed1975

[Medically treated severe arterial hypertension. Long term course].

Antihypertensive therapy was performed in 47 patients having severe or malignant hypertension. The duration of the survey was two years. A highly significant decrease in blood pressure was observed. The decrease was not dependent on the type of antihypertensive treatment. Renal function was reduced at the beginning of the treatment. The renal insufficiency partly or totally diminished in course of time. Coronary insufficiency was noted in 5 patients. Coronarography showed thrombotic atherosclerosis in only one patient. A significant increase in lipids, cholesterol and triglycerids was nearly constant. The meaning of such facts is discussed.

Antihypertensive Agents↗
PubMed1975

[Use of propranolol in permanent essential hypertension].

The anti-hypertensive effect of propranolol is studied in 35 essential permanent hypertensive patients. The decrease in blood pressure in higher in the presence (p is less than 0.01) than in the absence of diuretic therapy. The anti-hypertensive effect is higher in severe than in moderate hypertension. No side effect was observed except the decrease in heart rate (p is less than 0.001). Dihydralazine was added in 4 severe hypertensive patients and induced in 2 of them anginal attacks.

Adult↗