Recipient Organization
UNIVERSITY OF TENNESSEE
2621 MORGAN CIR
KNOXVILLE,TN 37996-4540
Performing Department
SMALL ANIMAL CLINICAL SCIENCES
Non Technical Summary
Follicular arrest (Alopecia X) is a common disease seen in Pomeranians and other plush coated breeds. While systemic illness is not associated with this disease, the loss of hair is unsightly and causes great concern to the owner. The pathomechanism of this condition is unknown. Melatonin is a benign treatment that results in some degree of hair regrowth in approximately 60% of the dogs. By understanding the mechanism by which melatonin causes hair regrowth, we may be able to elucidate the pathomechanism of the alopecia and thus develop a more reliable treatment or prevention protocol for dogs with this condition
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Goals / Objectives
We hypothesize that dogs with follicular arrest have increased activity of estrogen receptors in hair follicles, preventing the hair follicles from cycling normally. Thus, melatonin may cause hair regrowth in dogs with follicular arrest by its ability to block the activation of estrogen receptors. Thus, the specific objective is to determine if hair regrowth in dogs with follicular arrest when treated with melatonin is associated with a decrease in follicular estrogen receptors.
Project Methods
Sixteen Pomeranians of either sex with follicular arrest will be enrolled in the study over 6-9 months. They will be diagnosed with follicular arrest by clinical signs and ruling out hypothyroidism and hyperadrenocorticism. A biopsy will be taken from an alopecic area. Samples will be processed into formalin blocks as soon as they are acquired. Initial histopathologic evaluation to confirm the diagnosis will be done on all samples as they are obtained. The histopathology should support the diagnosis of follicular arrest and eliminate diseases that could mimic this condition (sebaceous adenitis, color dilution alopecia, etc.). A second biopsy will be obtained from a similar location after 3 months on melatonin. The biopsies will be evaluated for number of hair follicles and the ratio of hairs in anagen and telogen. Paired t-test will be used to evaluate these parameters. Immunohistochemical detection of estrogen receptors will also be performed. Using morphometric
analysis, we will compare estrogen receptor numbers after 3 months of melatonin to baseline for each dog and numbers of estrogen receptors in dogs with hair regrowth on melatonin to those that did not regrow hair.