Hair Growth Pattern in Nude Mice

Abstract

Nude mice are not bald but instead show an ‘abortive’ reduced hair growth on different sites of the integument. An albino (NMRI-nu) and a pigmented (C57BL/6-nu) strain of nude mice were examined as to whether the regional distribution pattern of this anagen hair proliferation is subject to the same ontogenetic development as in hairy mice. Hairy mice of both strains served as a comparison. Hair distribution was documented macroscopically by drawing and photography in a total of 415 mice of both sexes up to 421 days of age. Because of the pigmentation of the growing anagen hair follicles, the growth areas in the pigmented nude mice were distinctly visible whereas in the albino mice they were roughly recognisable from the boundaries of hair covering. The regional distribution of the ‘abortive’ anagen hair pattern in both nude strains corresponded to the wave-like course of the adult hair generations of hairy mice. As in older hairy mice, the hair cycle duration in nude mice was prolonged from an age of 121–180 days, the hair growth areas appeared reduced and less symmetrically orientated. Differences of up to 33% in body mass between the lighter nude and +/nu mice made ontogenetic comparison impossible so that all information is based on direct pattern or age comparison. The significance of experiments on the skin and hair follicles of nude mice is further increased if litters are examined comparatively and the temporal and spatial dimension of the follicle proliferation is considered more carefully than has been the case until now.

In vivohair growth-stimulating effect of medicinal plant extract on BALB/c nude mice

“…The macroscopic appearance of hair growth of the control nude mice was documented as a few short, crippled, bent hair shafts emerging from the HFs. Very few follicles, of locally variable density, occur in the dorsal skin (Köpf-Maier et al, 1990;Militzer, 2001;Rigdon & Packchanian, 1974); and only during a short anagen growth phase (Iversen & Iversen, 1967). Here, we were able to observe an incomparable hair growth pattern in CZ-treated mice with other treated groups (Figure 1).…”

Traveling stripes on the skin of a mutant mouse

“…Militzer (25) used nude mouse of the pigmented strain (C57BL͞ 6-Foxn1 nu ) to visualize regions in the anagen phase of the hair growth and recorded the pattern change for up to 400 days. He found that young Foxn1 nu mice have a few broad traveling bands of anagen phase on the skin, but later (Ͼ200 days), those patterns are replaced by one or a few periodically appearing, (26) reported a mutant line, named cryptothrix (crh), that had similar waves.…”

Enhanced wound healing effect of canine adipose-derived mesenchymal stem cells with low-level laser therapy in athymic mice

“…There are no obvious structural differences between normal and athymic mice in the appearance of the outer root sheath, dermal papilla, bulb and sebaceous glands. In the athymic mice the hairs are bent and coiled in the upper dermis and they usually fail to penetrate the epidermis [32]. So, athymic mice used for the studies about hair growth effect of new therapy [33,34].…”