The Potency and Time Course of the Neuromuscular Effects of SZ1676 and Its Hydroxy Analogs in Guinea-Pigs

SZ 1676,1-[3α,17β-bis(acetyloxy)-2β-(1,4-dioxa-8-azaspiro[4, 5]dec-8-yl)-5α-androstan-l6β-yl]-1-(2-propenyl)pyrrolidinium.Br, and its 3-OH (SZ 1677), 17-OH (SZ 1824) and 3,17-OH (SZ1823) analogs are now being evaluated for eventual clinical use. In the present study the neuromuscular (NM) potencies and time courses of these compounds were compared to those of rocuronium. These studies were carried out on guinea-pigs (g.p.) because the relative potencies of steroid type muscle relaxants (MR) in clinical use were found to be relatively constant in g.p. and man1.