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Intraperitoneal injection of sulfated cholecystokinin octapeptide (CCK-8; 10 micrograms/kg) resulted in an increase in the IC50 for isoproterenol (4.2 microM to 23.3 microM) in displacing 1 nM 3H-dihydroalprenolol binding to rat hypothalamic membranes. 3H-p-Aminoclonidine binding was also lower in membranes prepared from CCK-treated rats, but the decrease was not statistically significant. In vitro, CCK(1-100 nM) had no effect on either alpha- or beta-adrenergic binding or on the 5'-guanylylimidodiphosphate modulation of binding. The results indicate that CCK does not act directly upon adrenergic receptors, but may reduce beta-adrenergic affinity through indirect means.

A series of beta-spiro[pyrrolidinoindolines], 3a-d, was prepared and evaluated for their ability to bind to the glycine receptor. These compounds were also tested in vivo to determine if they would produce convulsant or anxiolytic effects. The target indolines were chosen because they represent rings A, B, E, and a portion of ring C of strychnine. Results of this study indicate that, in this series, an acetylindoline in the endo configuration and a tertiary amine, such as that of the pyrrolidine ring nitrogen, are required for biological activity. In all of the cases studied, the activity was of a convulsant rather than a relaxant nature. Excellent correlation was found to exist between the binding affinities to the strychnine site of the glycine receptor and clonic convulsions (ED50) and death (LD50) in the mouse.

Twenty-four patients about to undergo elective cataract surgery received either a 2-g (ten patients) or a 4-g (14 patients) intravenous infusion of cefoperazone one to six hours before surgery. The 4-g dose produced a mean peak aqueous humor concentration of 2.93 micrograms/ml at one hour; the mean concentration remained higher than 2 micrograms/ml for at least four hours. These levels, however, were never more than 90% of the minimum inhibitory concentration of cefoperazone for common bacterial ocular pathogens.

We administered cefamandole nafate to 69 patients before cataract extraction and assayed serum and aqueous humor for antibiotic content at the time of surgery. Average aqueous humor levels of 0.33, 0.59, 0.21, and 0.14 microgram/ml were achieved at one half, one, two and four hours, respectively, after a 1-g intravenous dose. After a 2-g intravenous dose, we found average aqueous humor levels of 1.26, 1.0, 1.57, 0.73, and 0.34 microgram/ml at one half, one, two, four and six hours, respectively. Therapeutic levels in primary aqueous humor effective against common grampositive pathogens were consistently achieved with the 2-g dose, but levels effective against Enterobactereaceae were attained only erratically.