Prednisolone in Hepatitis by MHV-3 Virus: Study of the Dynamics of Virus Multiplication in Relation to Time of Prednisolone Injection

Abstract

Summary

Swiss mice were injected intravenously with 10⁶ LD₅₀ of MHV-3 virus and, simultaneously, with 2 mg of prednisolone. Control mice were injected with physiological saline and virus, respectively. The animals were killed at different time intervals after the injection and the Spearman-Kärber method was used to determine viral LD₅₀ (and relative standard error) in blood, liver, and spleen.

Prednisolone produces an increase of viral LD₅₀. This effect occurs after 15-20 hr, with more or less identical intensity in liver, spleen, and blood.

Further studies were done by injecting prednisolone intravenously (single dose of 2 mg), not simultaneously with the virus, but 2, 4, 6, 10, 12, and 16 hr afterward and also 12 and 6 hr before.

Determination of LD₅₀ in liver, at different time intervals after the injection of virus, demonstrated that the effect of prednisolone always occurred 15-20 hr after its administration. This effect was temporary and disappeared in about 10 hr. Furthermore, prednisolone did not appear to influence the eclipse phase of the virus.