The possible influence of the epithalamic area on melanophore-stimulating hormone (MSH) release was investigated in Rana berlandieri forreri (Rana pipiens, sensu lato). Electrical stimulation of a specific region on the diencephalic roof resulted in a reversible darkening of skin melanophores. The latency between stimulation and onset of melanophore dispersion averaged from 1 to 3 min. Hypophysectomy, however, prevented the electrical stimulation-induced melanophore response from occurring. Thus, a neuronal, humoral, or integrated neuroendocrine pathway apparently develops from the diencephalon, in proximity to the pineal-subcommissural complex, to regulate pars intermedia MSH secretion.
ASJC Scopus subject areas
- Animal Science and Zoology