Differential effect of i.p.- and i.v.-injected adriamycin on the clonogenic spermatogonia of murine testis.

The response of murine clonogenic spermatogonia has been measured after intraperitoneal or intravenous injections of adriamycin (ADR). When measured over the whole testis, the survival curve for regenerating tubules after i.p. ADR had a 10-15% lower LD37 dose (that dose which sterilises 37% of tubules) but a two-fold higher average D0 for the clonogenic cells than that for i.v. ADR. Survival was then measured in concentric zones of these equatorial sections of testis. For i.v. injection survival parameters varied little between zones in the centre of the testis and zones adjoining the testicular capsule. In contrast, for i.p. ADR central zones had a 40% higher LD37 but the same D0 as for i.v. ADR, while peripheral zones had LD37s as little as 35% of the i.v. figure and mean D0s 2-3 times higher. Pharmacokinetic considerations that might lead to these differences in clonogenic response are discussed.