The hair erection muscle, arrector pili, is a kind of smooth muscle located in the mammalian dermis. The immunohistochemical study using an antibody against smooth muscle alpha actin (SMA) showed that the arrector pili muscle develops approximately 1-2 weeks after birth in dorsal and ventral skin, but thereafter they degenerate. The arrector pili muscle was not detected in the mystacial pad dur...

The effect on hair growth of wounding the lower region of whisker follicles, and in particular the dermal papilla, with sharply pointed tungsten needles was studied in adult hooded rats. Following injury hair growth ceased, but was subsequently resumed. While it might have been anticipated that follicle wounding would have a negative effect on whisker length, regular postoperative length measur...

Subcutaneously transplanted Ehrlich ascites tumor invaded the subcutis of the overlying skin and resulted in epidermal enlargement, consisting of cell hyperplasia and hypertrophy. The resting hair follicles, on the other hand, were completely un affected by the invading tumor. The growing tumor eventually invaded the dermis, resulting in a further increase in the thickness of the epidermis. How...

Purpose: To investigate the effect of Glycyrrhiza glabra root extract on hair growth in female Wistar rats. Methods: Female Wistar rats were used for the hair growth promotion studies. They were divided into three groups(n = 6) and their dorsal skin was completely denuded to completely remove hair. Paraffin oil (control), 2 % minoxidil solution (reference) or petroleum ether (60 – 80 C) root ex...

MicroRNAs (miRNAs) regulate the expression of many mammalian genes and play key roles in embryonic hair follicle development; however, little is known of their functions in postnatal hair growth. We compared the effects of deleting the essential miRNA biogenesis enzymes Drosha and Dicer in mouse skin epithelial cells at successive postnatal time points. Deletion of either Drosha or Dicer during...

The combined effects of myosin II and actin enable muscle and nonmuscle cells to generate forces required for muscle contraction, cell division, cell migration, cellular morphological changes, the maintenance of cellular tension and polarity, and so on. However, except for the case of muscle contraction, the details are poorly understood. We focus on nonmuscle myosin and actin in the formation ...

Background and Objective: Rosacea is a common and ill-defined disease and Demodex folliculorum has been reported in rosacea in a number of clinical studies. Since demodex mite is present in many healthy individuals, the mite may have a pathogenic role only when it is present in high densities. Therefore,...

The permeation pathway of macromolecules and nanospheres through skin was evaluated using fluorescent isothiocyanate (FITC)-dextran (average MW, 4 kDa) (FD-4) and nanospheres (500 nm in diameter) in hairless rat abdominal skin and porcine ear skin as well as a three-dimensional cultured human skin model (cultured skin model). A low molecular hydrophilic compound, sodium fluorescein (FL) (MW, 37...

1. In the epidermis non-specific esterase activity outlines a strongly reactive band between the stratum granulosum and the stratum corneum. In the epidermis of the palm, there is no such esterase-rich band. 2. The outer sheath of active hair follicles has strong enzyme activity. The degenerating hair bulb in catagen follicles is very strongly reactive, and clusters of cells around the hair clu...

The discovery that microRNAs (miRNAs) play important roles in regulating gene expression via posttranscriptional repression has revealed a previously unsuspected mechanism controlling development and progenitor-cell function (reviewed in ); however, little is known of miRNA functions in mammalian organogenesis. Processing of miRNAs and their assembly into the RNA-induced silencing (RISC) comple...