THE PARMACOLOGY OF -AMINOETHYLISOTHIURONIUM BROMIDE IN THE CAT

¹ Division of Pharmacology and Toxicology, Department of Radiation Biology, The University of Rochester School of Medicine and Dentistry, Rochester 20, New York, and Biology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee

Low doses of AET (2.5 mgm./kgm.) evoke a fall in blood pressure, bradycardia and apnea; this triad may be abolished by section of the vagi. Atropine blocks the bradycardia and hypotension but not the apnea. Gut contractions which may be abolished by atropine are also noted.

Larger doses of AET sometimes produce a biphasic blood pressure response, a fall followed by a rise. The nature of the hypertensive mechanism is obscure.

Inhibition of nictitating membrane contractions with doses of AET above 10 mgm./kgm. is mediated both by alterations in ganglionic transmission and a direct effect on the nictitating membrane.

A slight augmentation of skeletal muscle contractions is noted with larger doses of AET (15 to 20 mgm./kgm.). Convulsions and death follow doses in excess of 25 mgm./kgm.