Changes in hair growth (2)

Changes in hair growth (2)



MATERIALS AND METHODS
All work was performed on animals from an inbred strain of hooded rat
(colony Dundee University). Only the major vibrissa follicles of the mystacial
region were used, and identification of individual follicle position and
subsequent recording of information were carried out according to the annotation
of Oliver (1966a). Observations of whiskers were performed under a dissecting
microscope (magnification x20). Fine-pointed watchmakers' forceps were
used to locate and separate emergent growing hairs from the thicker, and generally
larger, non-growing club vibrissae. Lengths were measured using transparent
flexible polythene tubes of internal diameter 0-8 mm, graduated at intervals
of 1 mm, and estimates were to the nearest 0-5 mm.
As a preliminary investigation the club whiskers of 17 male rats, 12 aged six
months or more and 5 aged three months, were measured in order to obtain the
characteristics of maximum fibre length for each follicle position, and length
differences for paired positions on opposite sides of the face.