Ultrastructure of normals and castrates and the effects of testosterone and ultraviolet (UVL‐B) irradiation on scrotal skin of rats

Glimcher, Mark Edward; Flynn, Evelyn; Szabó, George

doi:10.1002/jez.1402070209

Cited by 5 publications

(1 citation statement)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As in the case of VIEM, epidermal melanocytes are also mostly bi-/tripolar in cell culture, even though they are highly dendritic in the skin. As mentioned above, in epidermal melanocytes, the characteristic dendritic morphology is stimulated by UV radiation [Glimcher et al, 1979;Hara et al, 1995] and VIEM may react in a similar manner to oxidative inner ear processes. Future experiments with our cultured VIEM and oxidative substances or UVB should verify these theses.…”

Section: Discussionmentioning

confidence: 99%

In vitro Isolation and Cell Culture of Vestibular Inner Ear Melanocytes

Hanke¹,

Kief

Leuwer³

et al. 2005

Audiol Neurotol

View full text Add to dashboard Cite

Introduction: Melanocytes of the membranous labyrinth of the inner ear have been described morphologically in various contexts. Nature and functions of these cells are as yet not completely clear, even though several hypotheses exist regarding the same. The limited knowledge is due in part to a lack of methods regarding in vitro cell culture. The aim of this study was to describe conditions for the successful cell culture of vestibular inner ear melanocytes (VIEM), to compare their growth properties with those of epidermal melanocytes, and to characterize them immunohistochemically. Materials and Methods: Membranous labyrinth cells from freshly slaughtered sheep were isolated, and melanocytes and fibroblasts subsequently cultured. In addition, melanocytes from the skin of the same sheep were cultured. Antibodies specific to tyrosinase, tyrosinase-related protein 1 (TRP-1/Mel-5), and melanoma-specific antigen A (Melan A) were used to analyze the cultured cells. Results: The proliferation of VIEM was retarded in comparison to epidermal melanocytes. After 14 days, VIEM began to proliferate for the first time, whereas epidermal melanocytes proliferated already after 7 days. In contrast to epidermal melanocytes, the culturing process of VIEM seemed to be dependent on the presence of fibroblasts, and VIEM often accumulated in the vicinity of fibroblasts forming three-dimensional clusters. Moreover, VIEM showed a higher ratio of highly pigmented cells with a round cell shape and small dendrites in comparison to epidermal melanocytes. Immunohistochemical techniques proved the VIEM to be positive for Melan A, TRP-1 and, in the majority of cases, also for tyrosinase. Conclusion: We successfully cultured melanocytes of the inner ear vestibular labyrinth for the first time and demonstrated melanocytic characteristics of these cells. This accomplishment will provide the opportunity to investigate VIEM in more detail in future experiments.

show abstract

Section: Discussionmentioning

confidence: 99%

In vitro Isolation and Cell Culture of Vestibular Inner Ear Melanocytes

Hanke¹,

Kief

Leuwer³

et al. 2005

Audiol Neurotol

View full text Add to dashboard Cite

show abstract

Seasonal patterns in the diagnosis of malignant melanoma of skin and eye in upstate New York

Polednak

1984

Cancer

View full text Add to dashboard Cite

Seasonal patterns in diagnosis were examined for 2403 melanomas of the skin and 238 melanomas of the eye diagnosed among residents of upsatate New York State in 1975 to 1979 and reported to the population‐based New York State Cancer Registry. The previously reported summer peak in diagnosis of melanoma of the lower extremity in females was confirmed and shown to hold for melanomas diagnosed at both early and late clinical stages; increased recognition of earlier stage melanomas in summer months is an unlikely explanation for this peak. For skin melanomas at other anatomic sites, seasonal patterns by sex and clinical stage at diagnosis were more complex. A previously unreported seasonal pattern was evident for trunk melanomas in males, with a March–April peak. Significant seasonal variations in diagnosis of melanomas of the eye were evident for both males and females, but the seasonal patterns differed between the sexes. Possible explanations for these findings on skin and eye melanomas were discussed with reference to psychosocial and hormonal factors as well as ultraviolet stimulation.

show abstract

Testosterone and UVL‐B stimulation of epidermal melanocytes in rat scrotal skin

1979

View full text Add to dashboard Cite

The effects of UVL-B and/or testosterone replacemnt therapy are compared in normal and castrated rats in order to determine whether testosterone is required for UVL-B (290-315 nm) stimulation of melanogenesis in the testosterone-dependent epidermal melanocyte system of the scrotal skin of black Long Evans rats. Testosterone is not a prerequisite for UVL-B stimulation of melanocytes as in both castrates and normal animals the melanocytes respond to UVL-B by increases in size, length and number of dendrites (dendriticness), and tyrosinase activity (intensity of Dopa reaction). Addition of testosterone to castrates does enhance the effects of UVL-B. However, UVL-B with or without testosterone cannot maintain normal melanogenesis in rats irradiated immediately after castration nor can it restore normal melanogenesis following long term castration. Bth the amount of UVL nergy/exposure and the number of exposures are important variables in stimulation of the epidermal melanocytes. Administration of a dose of UVL-B to castrates in a single exposure is ineffective, while the same overall dose spread over several exposures increases the size and dendriticness of melanocytes. Testosterone and UVL-B act synergistically in affecting melanogenesis although neither singly nor in combination are they able to fully restore normal melanogenesis.

show abstract

Ultrastructure of normals and castrates and the effects of testosterone and ultraviolet (UVL‐B) irradiation on scrotal skin of rats

Cited by 5 publications

References 22 publications

In vitro Isolation and Cell Culture of Vestibular Inner Ear Melanocytes

In vitro Isolation and Cell Culture of Vestibular Inner Ear Melanocytes

Seasonal patterns in the diagnosis of malignant melanoma of skin and eye in upstate New York

Testosterone and UVL‐B stimulation of epidermal melanocytes in rat scrotal skin

Contact Info

Product

Resources

About