Mechanism of spring relapse in avian malaria: effect of gonadotropin and corticosterone.
Previous work demonstrated that corticosterone induces relapse of avian malaria, and that this effect varies markedly from winter to spring. In the present study, English sparrows with latent Plasmodium relictum infections were treated in winter with corticosterone, gonadotropin, corticosterone + gonadotropin, or a control regimen consisting of the oil vehicle. Gonadotropin neither induced relapse nor potentiated the induction of relapse by corticosterone. These data cast doubt on the hypothesis that spring relapse in malarial infections is mediated by seasonal changes in reproductive hormone levels.
Applegate
J E
JE
Naval Medical Research Institute, Bethesda, Maryland 20014, USA.
Beaudoin
R L
RL
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D003345:Corticosterone / Q000494:pharmacology*; D004357:Drug Synergism; D006062:Gonadotropins / Q000494:pharmacology*; D008289:Malaria, Avian / Q000209:etiology*; D011897:Random Allocation; D012008:Recurrence; D012621:Seasons; D046370:Sparrows / Q000469:parasitology*; D016896:Treatment Outcome
D000893:Anti-Inflammatory Agents; D006062:Gonadotropins; D003345:Corticosterone