The effects of chronic treatment with N-tert-butyl-alpha-phenylnitrone on cerebellar noradrenergic receptor function in aged F344 rats.

We examined if a 2 week treatment with the spin trapping agent N-tert-butyl-alpha-phenylnitrone (PBN) would alleviate age-related deficits in cerebellar noradrenergic function of male 21-22 month old F344 rats compared to age-matched controls. Noradrenergic receptor function of PBN-treated rats was similar to young rats whereas for non-treated rats it was typical of that previously recorded in aged rats. Thus, treatment with PBN may reverse age-related deficits in cerebellar noradrenergic receptor function.

Therapeutic problems arising from the use of the intravenous route for drug administration.

The kinetics of drug delivery were studied under conditions of varying iv flow rates and varying sites of drug administration into an iv system. The iv sites and rates were selected on the basis of questionnaire data obtained from nursing personnel. The rate of drug delivery from the iv system was dependent upon the iv flow rate and site of injection of the drug into the iv system. Under conditions of slow iv flow rates (3 ml/hour) there was the expected time delay required for the drug to begin to be infused but an unanticipated protracted time required for actual completion of the drug infusion. Calculation of theoretical drug blood levels based on the results of these iv studies revealed very different blood levels of drug at respective times, including different peak concentrations, depending on the iv flow rate and site at which the drug was injected into the system. Failure to appreciate the effects of slow iv rates and distal iv injection sites on actual rates of drug administration can adversely affect pharmacokinetic decisions and conceivably influence therapeutic success or failure.