Role of Prolactin in Regulating the Onset of Winter Fur Growth in Mink: A Reconsideration

The study aimed to determine the role of prolactin (PRL) in the onset of winter fur growth (anagen) in mink. Researchers tested if elevating PRL levels, adrenalectomy (ADX), and administering dehydroepiandrosterone (DHEA) or its metabolite Δ5-DIOL would affect winter anagen. Treatments included haloperidol (HAL), melatonin (MEL), deoxycorticosterone (DOC), DHEA, and Δ5-DIOL. MEL reduced PRL levels and induced winter anagen 7 weeks earlier, while HAL also induced early anagen without altering PRL levels. ADX and ADX + DHEA treatments led to early anagen without changing PRL levels. DHEA or Δ5-DIOL had no effect on intact mink. The findings suggested that reduced PRL is not essential for winter anagen onset, and adrenal glands' inhibitory effects are not mediated by DHEA or Δ5-DIOL.