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E W HORTON

Publications and source records attributed to E W HORTON.

15 recordsLinked to original sources
PubMed1964

THIN-LAYER CHROMATOGRAPHY AND BIOASSAY OF PROSTAGLANDINS IN EXTRACTS OF SEMEN AND TISSUES OF THE MALE REPRODUCTIVE TRACT.

By acid ether extraction and thin-layer chromatography, prostaglandins have been separated from biologically active compounds of other chemical groups. The technique does not, however, separate different prostaglandins from each other. The biological activity of the eluates was estimated on the rabbit isolated jejunum and the hamster isolated colon preparations in terms of prostaglandin E(1); the concentrations (thus expressed) of prostaglandin in human semen ranged from 24 to 783 mug/ml. with a mean of 226 mug/ml. No prostaglandins (minimal detectable concentration, 0.5 mug/g) could be detected in the male reproductive organs of several species of laboratory animal.

Animals↗
PubMed1964

ACTIONS OF PROSTAGLANDINS E1, E2 AND E3 ON THE CENTRAL NERVOUS SYSTEM.

Prostaglandins E(1), E(2) and E(3), injected into the cerebral ventricles of unanaesthetized cats, produced sedation, stupor and signs of catatonia. The threshold dose was 3 mug/kg. Slight sedation was also observed following an intravenous injection, but a dose of 20 mug/kg was required. In chicks, intravenous injections of prostaglandins (10 to 400 mug/kg) caused respiratory depression, profound sedation, loss of normal posture and, with the higher doses, loss of the righting reflex.

Alprostadil↗
PubMed1963

A COMPARISON OF THE BIOLOGICAL ACTIVITIES OF FOUR PROSTAGLANDINS.

The biological activities of prostaglandins E(1), E(2), E(3) and F(1alpha) have been compared. Prostaglandins E(1), E(2), E(3) were qualitatively similar; E(1) and E(2) were about equiactive, but E(3) was less active on all preparations. Prostaglandin F(1alpha) was a less potent vasodilator than E(1) on the cat gastrocnemius muscle blood flow and skin blood flow and a less potent depressor drug on rabbit blood pressure. On the rabbit isolated jejunum F(1alpha) was twice as active as E(1) but on the guinea-pig isolated ileum E(1) was about forty times more active than F(1alpha). One qualitative difference between these prostaglandins was observed; on the rabbit fallopian tube in vivo prostaglandins of the E series decreased both the tone and the peristalsis of the tube whereas prostaglandin F(1alpha) increased tubal tone.

Animals↗
PubMed1963

THE EFFECT OF PROSTAGLANDIN E1 ON RESPONSES OF SMOOTH MUSCLE TO CATECHOL AMINES, ANGIOTENSIN AND VASOPRESSIN.

Reduction of the pressor responses to adrenaline in the rabbit following administration of prostaglandin E(1) has been confirmed. The effect is, however, nonspecific since noradrenaline, angiotensin and vasopressin are also antagonized. Analogous responses were observed in blood flow experiments on the cat hind limb but not on the rabbit isolated auricles or the rabbit isolated duodenum. Contractions of the cat nictitating membrane produced by sympathetic preganglionic stimulation or by adrenaline were not decreased following injection of prostaglandin E(1) but the relaxation period was shorter. Contractions of the rabbit vas deferens induced in vivo by adrenaline were smaller after prostaglandin E(1) and this effect tended to be long-lasting.

Alprostadil↗
PubMed1959

The extraction of human urinary kinin (substance Z) and its relation to the plasma kinins.

Human urinary kinin (substance Z) has been extracted by modifications of the methods previously described by Gomes (1955) and Jensen (1958). The separation of two oxytocic fractions from such extracts by paper pulp chromatography (Walaszek, 1957; Jensen, 1958) could not be confirmed. Substance Z could not be distinguished from kallidin, bradykinin or glass-activated kinin by parallel quantitative assays, thus confirming that these four substances are very closely related.

Biological Assay↗
PubMed1959

Human urinary kinin excretion.

It has been shown that the isolated rat duodenum relaxes in the presence of low concentrations of plasma and urinary kinin. The tissue is at least as sensitive as the rat uterus. Vasopressin and oxytocin, in large doses, also caused relaxation of the duodenum whereas acetylcholine, substance P and 5-hydroxytryptamine caused contraction. It was concluded that if an extract is assayed on the rat uterus and the rat duodenum in parallel using plasma kinin as a standard, and the results agree, this is good evidence that the active principle being estimated is a kinin. This method is therefore both sensitive and specific for kinin estimations, but it will not distinguish between kinins of different origin. The urinary excretion of kinin in 14 healthy adults was found to be fairly constant. The minute output was unaffected by the rate of urine formation, urinary pH, or time of day. There was no increase during sweating or salivation.

Adult↗