Pharmacological studies of certain amides of substituted ethylenediamines - I.

Five substituted amides of ethylenediamines produced hypotension in dogs, which was not blocked by atropine, mepyramine and propranolol. The amides potentiated the pressor responses to Adr and NA and antagonised the depressor responses to Ach and histamine. The compounds also antagonised Ach-induced contractions on the frog rectus abdominis muscle and of carbachol on rat isolated colon suggesting d-tc and atropine-like actions respectively. Antihistaminic activity was observed on guinea pig isolated ileum as on dog blood pressure. Adr and NA-induced relaxation of rabbit isolated jejunum was potentiated. Finally Adr and NA-induced contractions of rat isolated seminal vesicle was antagonised.