title: Maxadilan activates PAC1 receptors expressed in Xenopus laevis xelanophores.
abstract: Functional interactions between ligands and their cognate receptors can be investigated using the ability of melanophores from Xenopus laevis to disperse or aggregate their pigment granules in response to alterations in the intracellular levels of second messengers. We have examined the response of long-term lines of cultured melanophores from X. laevis to pituitary adenylate cyclase activating peptide (PACAP), a neuropeptide with vasodilatory activity, and maxadilan, a vasodilatory peptide present in the salivary gland extracts of the blood feeding sand fly. Pituitary adenylate cyclase activating peptide increased the intracellular levels of cyclic adenosine monophosphate (cAMP) and induced pigment dispersion in the pigment cells, confirming that melanophores express an endogenous PACAP receptor. Maxadilan did not induce a response in non-transfected melanophores. When the melanophores were transfected with complementary DNA (cDNA) from the three different members of the PACAP receptor family, maxadilan induced pigment dispersion specifically and cAMP accumulation in melanophores transfected with the cDNA for PAC1 receptors but not VPAC1 or VPAC2 receptors. A melanophore line was generated that stably expresses the PAC1 receptor.
authors.affiliation: Department of Dermatology, Cutaneous Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Charlestown, MA 02129, USA.
authors.forename: Phyllis
authors.initials: P
authors.lastname: Pereira
authors.forename: Vermuri B
authors.initials: VB
authors.lastname: Reddy
authors.forename: Kounga
authors.initials: K
authors.lastname: Kounga
authors.forename: Ysabel
authors.initials: Y
authors.lastname: Bello
authors.forename: Ethan
authors.initials: E
authors.lastname: Lerner
mesh_terms: D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D015870:Gene Expression; D019476:Insect Proteins / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D008547:Melanophores / Q000187:drug effects / Q000502:physiology*; D009479:Neuropeptides / Q000494:pharmacology; D010446:Peptide Fragments / Q000494:pharmacology; D010860:Pigments, Biological / Q000378:metabolism; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D020239:Receptor Cross-Talk / Q000187:drug effects / Q000502:physiology; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I; D011979:Receptors, Pituitary Hormone / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D014665:Vasodilator Agents / Q000494:pharmacology*; D029867:Xenopus Proteins; D014982:Xenopus laevis
chemical_list: C495404:ADCYAP1 protein, Xenopus; D019476:Insect Proteins; D009479:Neuropeptides; D010446:Peptide Fragments; D010860:Pigments, Biological; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051236:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I; D011979:Receptors, Pituitary Hormone; D014665:Vasodilator Agents; D029867:Xenopus Proteins; C069147:maxadilan protein, insect; D000242:Cyclic AMP