Oestrus cycle perturbations and hypotrophy of clitoral glands in malaria-infected female BALB/c mice

Abstract

An experimental host-parasite association involving BALB/c female mice infected with Plasmodium vinckei petteri was used with the aim of investigating the morphological and physiological alterations induced by the parasite in the genital tract of the host. The vaginal oestrous cycle was monitored as a daily clue to the sexual physiology of the female mice, and a complete histological analysis of the genital tract was performed 36 days following parasite inoculation. The oestrous cycle showed strong transitory alterations during the first 30 days following infection. The occurrence of oestrus days increased during the first 10 days post-infection and then decreased to a subnormal value during the following 20 days. Infected mice also showed a remarkable hypotrophy of their clitoral glands 30 days after the beginning of the malarial infection. A probable cause of such perturbations is a significant hormonal imbalance triggered by the erythrocytic proliferation of the Plasmodium. The relationship between the immune response of the host and these physiological and morphological alterations, as well as the outcomes of these alterations on the sexuality of the rodent host are discussed.

Hormonal and immunological mechanisms mediating sex differences in parasite infection

“…Although several studies illustrate that host sex steroids influence the course of Plasmodium infection, additional studies suggest that these protozoan parasites can alter hormone concentrations in their hosts. Infection of female mice with P. berghei increases concentrations of oestradiol and progesterone and disrupts oestrus cyclicity (107,108). Infection with P. chabaudi suppresses testosterone concentrations in males (109).…”