Efect of Histamine on Reproduction in Female Mice

Abstract

Histamine fed to laying chickens causes an abrupt cessation of egg production (Shifrine, Adler & Burkhalter, 1963). Experiments were thus designed to determine whether ingested histamine has an effect on the reproductive system of mice.In this paper we describe the effect of histamine fed to mice on ovulation and the oestrous cycle, pregnancy, the size of the adrenal "X " zone and medulla, food and water consumption, and the output of urine and faeces. METHODSFive experiments were conducted on 126 virgin and 10 pregnant Swiss White Mice (Webster Strain C3) using groups of five to fifteen in each experiment. The mice were housed in metal cages or plastic metabolic cages. They were maintained in the experimental environment for at least 3 days and given pulverized mouse feed. The experimental diets were pulverized commercial mouse rations mixed with histamine diphosphate to give 0.1 or 0.25% histamine as free base. A record was kept of the daily food and water consumed, and the output of urine and faeces. The mice were weighed daily and at necropsy.In pregnancy studies the pregnant mice were allowed to litter and were then immediately bred and held in metabolic cages to observe date of parturition and thus to assess date of conception. Vaginal smears were taken daily for 10 days from virgin females 60 days old and fed 0.1 and 0.25% histamine, and from control mice. The smears were stained with Giemsa and cells were examined to assess the stage of the oestrous cycle and the occurrence of ovulation (Snell, 1941). The latter was also determined by the character of maturing ovarian follicles, corpora haemorrhagica, and corpora lutea on gross and microscopic examination after mice were fed 0.1 or 0.25% histamine for periods ranging from 7 to 31 days.In all instances only the right adrenal gland was removed for sectioning. For histopathological studies, tissues were fixed in 10% neutral formalin and stained with haematoxylin and eosin. After staining, the adrenal " X " zone and medulla were measured with a microscopic ocular reticle at x 110. In each case only adrenal sections which were cut clearly across the centre of the gland, and only in areas representative of the whole gland, were chosen for measurements. This greatly reduced the number of adrenal glands used for tabulation.Ratios reported are of " X " zone relative to the total adrenal cortex, and medulla as a percentage of the total width of gland. RESULTSMice kept in plastic metabolic cages and fed 0.1 or 0.25% histamine were initially observed to behave in a more agitated manner than the controls. This included constant movement about the cage, increased nose scratching and more wastage of food and water.