Pre‐ and postweaning excretion of puberty‐influencing chemosignals in house mice

Abstract

Pre- and postweaning excretion of urinary chemosignals that influence puberty in female house mice were tested. The dependent variable used to assess the effectiveness of urine samples collected from donor mice was the age of first vaginal estrus in young female mice. Preweaning excretion of the puberty-delaying chemosignal by females was affected by litter sex composition; this effect interacted with the age of the young donor females. In litters of all females, the substance occurred from about the age of 9 days and in litters with 6 females and 2 males the delay substance was released from about the age of 17 days. Grouping dams during gestation but not prior to conception resulted in excretion of the puberty-delaying substance in the female progeny from the age of 17 days or possibly earlier. Young male mice do not excrete the puberty-accelerating chemosignal prior to the age of puberty. However, giving young males injections of testosterone resulted in an earlier first excretion of the acceleratory signal, suggesting that the machinery for chemosignal production is operative prior to the time of sexual maturity. Caging young males with an adult female prior to puberty resulted in earlier excretion of the puberty-accelerating substance, while caging young males with adult males retarded excretion of the substance. The findings are discussed in terms of early hormone effects on behavior and with regard to consequences for the chemosignal systems in house mice.

Family composition and menarcheal age: Anti‐inbreeding strategies

“…In mice, puberty-delaying urinary chemosignals can be released by very young, preweaned female mice, although their pubertydelaying effects may not be as robust as those of urine from adult female mice (Drickamer, 1992). It may not be coincidental that the presence of sisters in the current study (especially older sisters) was associated with delayed menarche.…”

Precocious weaning and changes in social variables during prepuberty affect cocaine reinforcing properties in adult mice

“…In this view, it should be noted that brain dopaminergic and adrenergic pathways are reported to playa major role in the neuroendocrine control of reproduction, and that cocaine administration has been shown to interact negatively with puberty-related processes in mice (see Chen & Vandenbergh, 1993). Taken together, these reports indirectely suggest that interference by peri pubertal sexual segregation with gonadal hormones and their metabolites on pubertal development (Drickamer 1992;Lupo di Prisco et aI., 1978;Vandenbergh, 1989) of modulatory monoaminergic systems in the CNS should be considered.…”

“…Prepubertal sexual segregation altered the function of monoaminergic eNS systems mediating the drug actiona neural substrate considered an important participant in an organism's responding to environmental challenge (Laviola et aI., 1994 )-as revealed by the restriction to mixed-sex reared mice of the modulatory effects of cocaine (see, e.g., Figure 3, lower panel on the right). This specific manipulation of rearing environment has also been related to changes in gonadal hormone regulation (Drickamer, 1992;Lupo di Prisco, Lucarini, & Dessi'-Fulgheri, 1978), and Savageau and Beatty (1981) reported that gonadectomy of male rats also affected the behavioral response to an amphetamine challenge (see . In this view, it should be noted that brain dopaminergic and adrenergic pathways are reported to playa major role in the neuroendocrine control of reproduction, and that cocaine administration has been shown to interact negatively with puberty-related processes in mice (see Chen & Vandenbergh, 1993).…”

Sibling effects on the behavior of infant mouse litters (Mus domesticus).

“…In fact, preweaning female mice reared in all-female litters are reported to be delayed in attaining first estrus in relation to females reared in litters with 1 or more males. As outlined by Drickamer (1992), there must be some internal events, as yet unmeasured, that are altered by a litter sex composition that involves no males. The hormonal and neurological effects of starting development in an all-female litter must be explored further.…”