Elevación de la concentración hemática de penicilina por la sulfametoxipiridazina

Estos resultados dejan ver claramente que la sulfametoxipiridazina en la experiencia descrita elevó al doble el promedio de concentración de penicilina en la sangre al final de la tercera hora. También sugieren estos resultados que, aunque la sulfametoxipiridazina se excreta muy lentamente, desde el principio bloquea parcialmente el mecanismo de transporte tubular renal, lo cual, a su vez, permite pensar que la dificultad de la eliminación de la sulfametoxipiridazina no está en su capacidad de acceso a este mecanismo de transporte.

Triple sulfonamides can reduce the renal excretion of penicillin 1,2,3. However, Bayne, Gylfe and Boger 4 disproved that effect. Nothing has been said about this effect, so far we Know, in relation with the slowly excreted sulfamethoxipiridazine. To study this the following experiences were designed: Dogs, weighing between 7 and 11 Kg., were divided into three groups. Serum penicillin activity was measured during three hours following the intravenous application of ten thousands units per Kg. The second group, besides penicillin, received half an hour before 10 mg. per Kg. of sulfamethoxipiridazine intravenously. The third group was nephrectomized bilaterally, before penicillin. For comparison purposes we took serum penicillin activity sixty minutes after application, as the 100 percent value and observed it for two hours more. The results was expressed as the residual percentage of activity. Results: In the group treated with penicillin alone the remaining serum penicillin activity after three hours was 15,63 percent, standard error: 3.35. percent. In the second group, penicilline plus sulfamethoxipiridazine, the remaining serum penicillin activity was 32,69 percent. standard error: 4.81. In the nephrectomized group the remaining activity was 87,5 percent, standard error: 12.5, four animals only. The statistical analysis shows the level of significance between first and second group is P0,01; between the second and third group P0,001; and between first and thirt group P0,001. Sulphamethoxipyridazine significantly interfered with the penicillin elimination. At the moment experiences are in progress in order to measure simultaneously the glomerular filtration rate.