PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “SYMPATHOMIMETICS/effects”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed1958

Sensitization of the heart and nictitating membrane of the cat to sympathomimetic amines by antihistamine drugs.

Sensitization to the cardio-accelerator action of adrenaline and noradrenaline by five antihistamines was examined on the acutely denervated heart of the cat. Antazoline (Antistin), chlorcyclizine and promethazine (Phenergan) increased the cardio-accelerator responses to both amines equally. Mepyramine (Anthisan) increased noradrenaline more than adrenaline action. Diphenhydramine (Benadryl) resembled cocaine in potentiating the responses to noradrenaline but not to adrenaline.On the nictitating membrane mepyramine caused sensitization to the actions of adrenaline, noradrenaline and tyramine, an effect similar to that of chronic preganglionic denervation. Diphenhydramine enhanced the action of noradrenaline more than that of adrenaline and had little effect on tyramine action, giving a sensitization which bears a greater resemblance to the type caused by cocaine or chronic postganglionic denervation.It is suggested that two distinct mechanisms are required to account for the phenomena of sensitization.

Amines↗
PubMed1958

The action of sympathomimetic amines on heart rate in relation to the effect of reserpine.

When the heart-lung preparation is made from a dog treated with reserpine, catechol amines such as noradrenaline and isoprenaline have a greater effect on the rate of the heart than they have in a preparation from a normal dog. Other sympathomimetic amines such as tyramine and ephedrine, on the other hand, are found to have lost their action. Since treatment with reserpine has been shown to cause the store of noradrenaline in the heart to disappear, and the infusion of noradrenaline into the preparation made from a reserpine-treated animal restores the action of tyramine, it is concluded that substances like tyramine and ephedrine normally act by liberating noradrenaline from the store, and do not act directly. Cocaine, like reserpine, increases the effect of noradrenaline and decreases the effect of tyramine on the heart rate; it appears to block the release of noradrenaline from the store in the heart.

Amines↗