Propanolol, a beta-adrenergic antagonist, retards response to MSH in skin of Anolis carolinensis

摘要: Abstract Lacking sympathetic innervation, the skin of A. carolinensis , an iguanid lizard, darkens within minutes in response to circulating melanocyte stimulating hormone (MSH) or beta adrenergic agonists such as epinephrine (EPI). This change is produced by dispersion melanin from a perinculear position dermal melanophores into superficial dendritic processes. These possess alpha-2 and beta-2 well MSH receptors except patch behind eye, eyespot, which lacks alpha receptors. Activation leads stimulation adenyl cyclase whereas inhibits enzyme override others. In series trials, injection saline propranolol was followed after 30 saline, EPI, MSH. Propranolol inhibited chromataphore EPI. It also, unexpectedly, retarded MSH, increasing latency eyespot formation body color duration darkening for both. Alteration blocker could be explained linkage both receptor common molecule form functional unit membrane melanophore.