Like Follicle, like Fibre? Diameter and not Follicle Type Correlates with Fibre Ultrastructure

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Abstract:

The hair follicles of most mammals are of two types, primary and secondary. Primary follicles develop earlier and have a prominent arrectorpili muscle. Secondary follicles have less prominent muscles and are often clumped, sharing a common opening from which fibres emerge. It is not entirely clear what types of follicles occur in human scalps. Partly this is because human hairs have a uniform appearance, unlike many mammals in which robust primary hairs differ markedly from narrow secondary fibres. Some sheep breeds are an exception because like humans, wool fibres have a similar macro-scale appearance irrespective of follicle type. How deep does this similarity go Using electron microscopy, we examined wool primary fibres from different breeds and contrasted them to secondary fibres. For fibres of similar diameter, there was no significant difference in the ultrastructure or proportion and distribution of cortex cell types in primary and secondary fibres. We conclude that fibre diameter is the most important fibre parameter with respect to structural differences between fibres, not whether the fibres originate from primary or secondary follicles.

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88-94

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November 2015

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[1] Ryder, M.L., Hair. 1 ed. Studies in Biology, ed. I. o. Biology. 1973, London: Edward Arnold. 58.

Google Scholar

[2] Rogers, G.E., Biology of the wool follicle: an excursion into a unique tissue interaction system waiting to be re-discovered. Experimental Dermatology, 2006. 15(12): pp.931-949.

DOI: 10.1111/j.1600-0625.2006.00512.x

Google Scholar

[3] Hardy, M.H., The secret life of the hair follicle. TIGs, 1992. 8(2): pp.55-61.

Google Scholar

[4] Bonnet, R., Über dia muskulatur der haut und der knäueldrüsen. Bayerisches ärztliches intelligenzblatt 1885.

Google Scholar

[5] Chapman, R.E., The ovine arrector pili musculature and crimp formation in wool, in Biology of the skin and hair growth, A.G. Lyne and B.F. Short, Editors. 1965, Angus and Robertson: Sydney. pp.201-232.

Google Scholar

[6] Ryder, M.L., Fleece evolution in domestic sheep. Nature, 1964. 204: pp.555-559.

DOI: 10.1038/204555a0

Google Scholar

[7] Song, W. -C., et al., A new model for the morphology of the arrector pili muscle in the follicular unit based on three-dimensional reconstruction. Journal of Anatomy, 2006. 208(5): pp.643-648.

DOI: 10.1111/j.1469-7580.2006.00575.x

Google Scholar

[8] Harland, D.P., et al., Transmission electron microscopy staining methods for the cortex of human hair: a modified osmium method and comparison with other stains. Journal of Microscopy, 2011. 243(2): pp.184-196.

DOI: 10.1111/j.1365-2818.2011.03493.x

Google Scholar