THE CIRCULATORY ACTION, AFTER ATROPINE, OF CERTAIN FURFURYL AMMONIUM IODIDES AND OF ACETYL-BETA-METHYLCHOLINE CHLORIDE (MECHOLYL)

¹ From the Department of Pharmacology, Temple University School of Medicine, Philadelphia, Pennsylvania

1. In cats and dogs with central nervous system destroyed it was found that certain doses of furfuryl trimethyl (F T M), furfuryl dimethyl ethyl (F D M E), tetrahydro-furfuryl trimethyl (T F T M) and tetrahydro-furfuryl dimethyl ethyl (T F D M E) ammonium iodides and also acetyl-beta-methyl choline chloride (A B M C), after atropine, may cause a rise of blood pressure which is reversed by a paralyzing dose of nicotine.

2. The pressor action of F T M, T F T M and A B M C, after atropine, was found to be of approximately equal intensity. All three are much less potent in their pressor action, after atropine, than carbaminoyl choline chloride (C C). F D M E and T F D M E are less active pressor agents, after atropine, than F T M, T F T M or A B M C.

3. F T M, T F T M, F D M E, T F D M E or A B M C have a "nicotine paralyzing" action as indicated by a mullifying effect of large amounts of these compounds on the pressor action of small doses of nicotine.

4. After adrenalectomy pressor effects, after atropine, are somewhat reduced in the case of F T M, F D M E, T F T M and T F D M E. With the doses of A B M C used the pressor action after atropine, was entirely nullified after adrenalectomy.

5. When pressor effects, after atropine, were established with F T M or A B M C, eserine potentiated the pressor action of these compounds. Because of its stability in blood, F T M potentiation by eserine must be explained on some basis other than esterase inhibition and it is doubtful if this mechanism of action entirely explains augmentation of the pressor action, after atropine, of A B M C.