Synthetic Eledoisin Research Articles

Simultaneous release of several tachykinins and calcitonin gene-related peptide from rat spinal cord slices

Superfusion of slices of the dorsal half of rat spinal cord in vitro with 10 μM capsaicin or 60 mM potassium lead to the simultaneous release of substance P (SP)-, neurokinin A (NKA)- and calcitonin gene-related peptide (CGRP)-like immunoreactivities (LI). The ratio between capsaicin-stimulated and basal release was higher for CGRP-LI than for SP-LI, indicating that relatively more CGRP is released from sensory nerves, whereas SP is not only released from afferent neurons. High-performance liquid chromatography of NKA-LI revealed several immunoreactive components. One major peak had the retention time of synthetic NKA. A second peak eluted close to the position of synthetic eledoisin. In conclusion, capsaicin releases several bioactive peptides from sensory neurons which may mediate the acute algetic effect of chemical irritants.

Effect of eledoisin, physalaemin and some eledoisin- or physalaemin-like peptides on water intake and arterial blood pressure in conscious pigeons

Summary The hypotensive and dipsogenic effects of eledoisin, physalaemin and some synthetic eledoisin- or physalaemin-like peptides were studied in conscious pigeons, respectively after intravenous or intracerebroventricular administration. The effects of the peptides were compared to the hypotensive or dipsogenic activities of eledoisin considered equal to 100. o 1) Shortening of eledoisin molecule by means of progressive elimination of up to four N-terminal aminoacid residues left practically unmodified the dipsogenic effect, while it progressively reduced the hypotensive effect. 2) Physalaemin was a dipsogen as potent as eledoisin, but its hypotensive activity was approximately double the one of eledoisin. 3) Modifying of physalaemin molecule produced different alterations in the dipsogenic and hypotensive effect. Apparently there was no relationship between the dipsogenic and the hypotensive effect of the substances tested.

Effects of eledoisin, physalaemin and some related peptides on water intake and arterial blood pressure in conscious rats

Summary The hypotensive and antidipsogenic effects of eledoisin, physalaemin and some synthetic eledoisin- or physalaemin-like peptides were studied in conscious rats, respectively after intravenous or intracerebroventricular administration. The effects of the peptides were compared to the hypotensive or anti-dipsogenic activities of eledoisin considered equal to 100. Eledoisin and its C-terminal nonapeptide proved to be the most active antidipsogens. Conversely, physalaemin and physalaemin-like substances were poor inhibitors of water intake, but potently lowered arterial blood pressure. Apparently, there was no relationship between hypotensive and antidipsogenic effects of the substances tested.

Effects of synthetic eledoisin and bradykinin on certain invertebrate preparations and the isolated frog heart.

Effects of Synthetic Eledoisin and Bradykinin on Certain Invertebrate Preparations and the Isolated Frog Heart

EFFECTS OF SYNTHETIC ELEDOISIN ON PLASMA FREE FATTY ACID AND BLOOD GLUCOSE LEVELS IN DOGS

EFFECTS OF SYNTHETIC ELEDOISIN ON PLASMA FREE FATTY ACID AND BLOOD GLUCOSE LEVELS IN DOGS

Sympathoadrenal response to eledoisin-induced hypotension in normotensives and hypertensives.

Blood pressure response to infusion of synthetic eledoisin was carefully evaluated in 8 normotensives. There was tachyphylaxis to the hypotensive effect of this peptide. This tachyphylaxis is partly accounted for by the overactivity of the sympathoadrenal system, because urinary excretion of catecholamines was found to increase during the hypotension induced by eledoisin. In contrast, the sympathoadrenal response was lacking in 13 hypertensive patients. The latter responded to eledoisin infusion with a profounder hypotension than the former, and this hypersensitivity was considered to be due to the lack of sympathoadrenal overactivity.

EFFECT OF ELEDOISIN ON THE SYSTEMIC VENOUS RETURN ON DOGS.

SummaryThe effects of eledoisin on the cardiovascular system were studied in anesthetized dogs. It was found that eledoisin decreased MSAP and increased HR, CO, MPAP, and LAP. In addition, when cardiac input was kept constant by means of a Sig-mamotor pump, eledoisin increased the blood level of the venous reservoir, indicating an increase in SVR. The increases in MPAP and LAP observed after eledoisin are most likely due to the increase in SVR.The author wishes to acknowledge the able technical assistance of Mr. G. R. Mercer. Synthetic eledoisin and sodium heparin (Liquaemin and Pan-heparin) were generously supplied, respectively, by Dr. R. Bircher of Sandoz Pharmaceuticals, Dr. H. A. Strade of Organon, Inc. and Dr. H. G. Schoepke of Abbott Laboratories.

Pressor effect of synthetic eledoisin in chickens

Pressor effect of synthetic eledoisin in chickens

Effects of synthetic eledoisin on the cardiovascular system

9he cardiovascular effects of synthetic eledoisin were studied in anesthetized dogs. It was found that eledoisin decreases mean systemic arterial pressure, and total and regional peripheral resistances. On the other hand, eledoisin increases heart rate, mean pulmonary arterial pressure, left atrial pressure, cardiac output and blood flows of the coronary, brachial and femoral arteries. The effects of eledoisin on pulmonary arterial pressure, left atrial pressure and cardiac output are biphasic, an initial increase being followed by a decrease. The mechanism of the changes of different parameters produced by eledoisin are discussed.

GENERAL AND REGIONAL CIRCULATORY EFFECTS OF SYNTHETIC ELEDOISIN IN MAN.

The circulatory effects of intravenous infusions of synthetic eledoisin were studied in nine normal subjects. Infusions of 0.6 μg/min of eledoisin in eight experiments on eight subjects produced a transient fall in mean arterial blood pressure, tachycardia (average 14.3 beats/min), marked increase in cardiac index (average 3.4 liters/min m2), increase in stroke volume (average 58.3 ml/beat) and fall in systemic vascular resistance (average 6 mm Hg/liter min). Blood flow to hand and forearm increased (average increase in four experiments on four subjects 7.9 and 2.9 ml/min 100 ml tissue, respectively). More marked hypotension and tachycardia and a more pronounced increase in hand and forearm blood flows were observed during infusions of 2–5 μg/min of eledoisin in four experiments on four subjects. These results indicate that eledoisin is a powerful dilator of vessels in skin and skeletal muscle, and quite probably of vessels in other vascular areas. vasodilatation; effects on cardiac output; effects on hand blood flow; effects on forearm blood flow; hypotensive agent Submitted on July 1, 1963

On peptide synthesis. C-terminal partial sequences of eledoisins and eledoisin analogs

A series of synthetic Eledoisin and Eledoisin-related subunits are described. The biological activities of the peptides are discussed.